RESUMEN
The value of cardiovascular magnetic resonance (CMR) in assessing and predicting acute right ventricular (RV) dysfunction in patients with anterior ST-segment elevation myocardial infarction (STEMI) remains ascertained. Eighty eight patients with anterior STEMI were prospectively recruited and underwent CMR examinations within one week following the coronary intervention. Patients with RV ejection fraction (RVEF) less than 2 standard deviations below the average at the center (RVEF ≤ 45.0%) were defined as having RV dysfunction. The size of infarction, segmental wall motion, and T1 and T2 mapping values of global myocardium and the interventricular septum (IVS) were measured. Predictive performance was calculated using receiver-operating characteristic curve analysis and logistic regression test. Twenty two patients presented with RV dysfunction. The RV dysfunction group had a larger IVS infarct extent (54.28 ± 10.35 vs 33.95 ± 15.09%, P < 0.001) and lower left ventricle stroke volume index (33.93 ± 7.96 vs 42.46 ± 8.14 ml/m2, P < 0.001) compared to the non-RV dysfunction group. IVS infarct extent at 48.8% best predicted the presence of RV dysfunction with an area under the curve of 0.864. Left ventricular stroke volume index (LVSVI) and IVS infarct extent were selected by stepwise multivariable logistic regression analysis. Lower LVSVI (odds ratio [OR] 0.90; 95% confidence interval [CI], 0.79 to 0.99; P = 0.044) and higher IVS infarct extent (OR 1.16; 95% CI 1.05 to 1.33; P = 0.01) were found to be independent predictors for RV dysfunction. In patients with anterior STEMI, those with larger IVS infarct extent and worse LV function are more likely to be associated with RV dysfunction.
Asunto(s)
Infarto de la Pared Anterior del Miocardio , Imagen por Resonancia Cinemagnética , Valor Predictivo de las Pruebas , Infarto del Miocardio con Elevación del ST , Volumen Sistólico , Disfunción Ventricular Derecha , Función Ventricular Derecha , Tabique Interventricular , Humanos , Masculino , Infarto del Miocardio con Elevación del ST/fisiopatología , Infarto del Miocardio con Elevación del ST/diagnóstico por imagen , Infarto del Miocardio con Elevación del ST/complicaciones , Infarto del Miocardio con Elevación del ST/terapia , Femenino , Persona de Mediana Edad , Disfunción Ventricular Derecha/fisiopatología , Disfunción Ventricular Derecha/diagnóstico por imagen , Disfunción Ventricular Derecha/etiología , Estudios Prospectivos , Anciano , Tabique Interventricular/diagnóstico por imagen , Tabique Interventricular/fisiopatología , Infarto de la Pared Anterior del Miocardio/fisiopatología , Infarto de la Pared Anterior del Miocardio/diagnóstico por imagen , Infarto de la Pared Anterior del Miocardio/complicaciones , Infarto de la Pared Anterior del Miocardio/terapia , Función Ventricular Izquierda , Factores de Riesgo , Intervención Coronaria PercutáneaRESUMEN
BACKGROUND: The effect of left ventricular septal myocardial pacing (LVSP) and left bundle branch pacing (LBBP) on ventricular synchrony and left ventricular (LV) hemodynamic status is poorly understood. OBJECTIVES: The aim of this study was to investigate the impact of LVSP and LBBP vs biventricular pacing (BVP) on ventricular electrical synchrony and hemodynamic status in cardiac resynchronization therapy patients. METHODS: In cardiac resynchronization therapy candidates with LV conduction disease, ventricular synchrony was assessed by measuring QRS duration (QRSd) and using ultra-high-frequency electrocardiography. LV electrical dyssynchrony was assessed as the difference between the first activation in leads V1 to V8 to the last from leads V4 to V8. LV hemodynamic status was estimated using invasive systolic blood pressure measurement during multiple transitions between LBBP, LVSP, and BVP. RESULTS: A total of 35 patients with a mean LV ejection fraction of 29% and a mean QRSd of 168 ± 24 ms were included. Thirteen had ischemic cardiomyopathy. QRSd during BVP, LVSP, and LBBP was the same, but LBBP provided shorter LV electrical dyssynchrony than BVP (-10 ms; 95% CI: -16 to -4 ms; P = 0.001); the difference between LVSP and BVP was not significant (-5 ms; 95% CI: -12 to 1 ms; P = 0.10). LBBP was associated with higher systolic blood pressure than BVP (4%; 95% CI: 2%-5%; P < 0.001), whereas LVSP was not (1%; 95% CI: 0%-2%; P = 0.10). Hemodynamic differences during LBBP and LVSP vs BVP were more pronounced in nonischemic than ischemic patients. CONCLUSIONS: Ultra-high-frequency electrocardiography allowed the documentation of differences in LV synchrony between LBBP, LVSP, and BVP, which were not observed by measuring QRSd. LVSP provided the same LV synchrony and hemodynamic status as BVP, while LBBP was better than BVP in both.
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Terapia de Resincronización Cardíaca , Electrocardiografía , Hemodinámica , Humanos , Masculino , Femenino , Anciano , Persona de Mediana Edad , Terapia de Resincronización Cardíaca/métodos , Hemodinámica/fisiología , Disfunción Ventricular Izquierda/fisiopatología , Disfunción Ventricular Izquierda/terapia , Función Ventricular Izquierda/fisiología , Tabique Interventricular/fisiopatologíaRESUMEN
Hypertrophic cardiomyopathy is the most common genetic cardiac disease and is characterized by left ventricular hypertrophy. Although this hypertrophy often associates with sarcomeric gene mutations, nongenetic factors also contribute to the disease, leading to diastolic dysfunction. Notably, this dysfunction manifests before hypertrophy and is linked to hypercontractility, as well as nonuniform contraction and relaxation (myofibril asynchrony) of the myocardium. Although the distribution of hypertrophy in hypertrophic cardiomyopathy can vary both between and within individuals, in most cases, it is primarily confined to the interventricular septum. The reasons for septal thickening remain largely unknown. In this article, we propose that alterations in muscle fiber geometry, present from birth, dictate the septal shape. When combined with hypercontractility and exacerbated by left ventricular outflow tract obstruction, these factors predispose the septum to an isometric type of contraction during systole, consequently constraining its mobility. This contraction, or more accurately, this focal increase in biomechanical stress, prompts the septum to adapt and undergo remodeling. Drawing a parallel, this is reminiscent of how earthquake-resistant buildings are retrofitted with vibration dampers to absorb the majority of the shock motion and load. Similarly, the heart adapts by synthesizing viscoelastic elements such as microtubules, titin, desmin, collagen, and intercalated disc components. This pronounced remodeling in the cytoskeletal structure leads to noticeable septal hypertrophy. This structural adaptation acts as a protective measure against damage by attenuating myofibril shortening while reducing cavity tension according to Laplace Law. By examining these events, we provide a coherent explanation for the septum's predisposition toward hypertrophy.
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Cardiomiopatía Hipertrófica , Humanos , Cardiomiopatía Hipertrófica/fisiopatología , Contracción Miocárdica/fisiología , Animales , Remodelación Ventricular/fisiología , Tabiques Cardíacos/fisiopatología , Tabiques Cardíacos/diagnóstico por imagen , Tabiques Cardíacos/patología , Tabique Interventricular/fisiopatología , Tabique Interventricular/diagnóstico por imagenRESUMEN
BACKGROUND: Endocardial catheter-based pulsed field ablation (PFA) of the ventricular myocardium is promising. However, little is known about PFA's ability to target intracavitary structures, epicardium, and ways to achieve transmural lesions across thick ventricular tissue. METHODS: A lattice-tip catheter was used to deliver biphasic monopolar PFA to swine ventricles under general anesthesia, with electroanatomical mapping, fluoroscopy and intracardiac echocardiography guidance. We conducted experiments to assess the feasibility and safety of repetitive monopolar PFA applications to ablate (1) intracavitary papillary muscles and moderator bands, (2) epicardial targets, and (3) bipolar PFA for midmyocardial targets in the interventricular septum and left ventricular free wall. RESULTS: (1) Papillary muscles (n=13) were successfully ablated and then evaluated at 2, 7, and 21 days. Nine lesions with stable contact measured 18.3±2.4 mm long, 15.3±1.5 mm wide, and 5.8±1.0 mm deep at 2 days. Chronic lesions demonstrated preserved chordae without mitral regurgitation. Two targeted moderator bands were transmurally ablated without structural disruption. (2) Transatrial saline/carbon dioxide assisted epicardial access was obtained successfully and epicardial monopolar lesions had a mean length, width, and depth of 30.4±4.2, 23.5±4.1, and 9.1±1.9 mm, respectively. (3) Bipolar PFA lesions were delivered across the septum (n=11) and the left ventricular free wall (n=7). Twelve completed bipolar lesions had a mean length, width, and depth of 29.6±5.5, 21.0±7.3, and 14.3±4.7 mm, respectively. Chronically, these lesions demonstrated uniform fibrotic changes without tissue disruption. Bipolar lesions were significantly deeper than the monopolar epicardial lesions. CONCLUSIONS: This in vivo evaluation demonstrates that PFA can successfully ablate intracavitary structures and create deep epicardial lesions and transmural left ventricular lesions.
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Ablación por Catéter , Ventrículos Cardíacos , Tabique Interventricular , Animales , Tabique Interventricular/fisiopatología , Tabique Interventricular/diagnóstico por imagen , Tabique Interventricular/cirugía , Ablación por Catéter/métodos , Ablación por Catéter/instrumentación , Porcinos , Ventrículos Cardíacos/fisiopatología , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/cirugía , Estudios de Factibilidad , Músculos Papilares/fisiopatología , Músculos Papilares/cirugía , Músculos Papilares/diagnóstico por imagen , Factores de Tiempo , Pericardio/cirugía , Pericardio/fisiopatología , Catéteres Cardíacos , Ultrasonografía Intervencional , Técnicas Electrofisiológicas Cardíacas , Diseño de Equipo , FemeninoAsunto(s)
Circulación Colateral , Circulación Coronaria , Ecocardiografía , Tabique Interventricular , Humanos , Tabique Interventricular/diagnóstico por imagen , Tabique Interventricular/fisiopatología , Circulación Coronaria/fisiología , Ecocardiografía/métodos , Circulación Colateral/fisiología , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND: Left bundle branch pacing (LBBP) and left ventricular septal pacing (LVSP) are referred to as left bundle branch area pacing. OBJECTIVE: This study investigated whether long-term clinical outcomes differ in patients undergoing LBBP, LVSP, and biventricular pacing (BiVP) for cardiac resynchronization therapy (CRT). METHODS: Consecutive patients with reduced left ventricular ejection fraction (LVEF <50%) undergoing CRT were prospectively enrolled if they underwent successful LBBP, LVSP, or BiVP. The primary composite end point was all-cause mortality or heart failure hospitalization. Secondary end points included all-cause mortality, heart failure hospitalization, and echocardiographic measures of reverse remodeling. RESULTS: A total of 259 patients (68 LBBP, 38 LVSP, and 153 BiVP) were observed for a mean duration of 28.8 ± 15.8 months. LBBP was associated with a significantly reduced risk of the primary end point by 78% compared with both BiVP (7.4% vs 41.2%; adjusted hazard ratio [aHR], 0.22 [0.08-0.57]; P = .002) and LVSP (7.4% vs 47.4%; aHR, 0.22 [0.08-0.63]; P = .004]. The adjusted risk of all-cause mortality was significantly higher in LVSP than in BiVP (31.6% vs 7.2%; aHR, 3.19 [1.38-7.39]; P = .007) but comparable between LBBP and BiVP (2.9% vs 7.2%; aHR, 0.33 [0.07-1.52], P = .155). Propensity score adjustment also obtained similar results. LBBP showed a higher rate of echocardiographic response (ΔLVEF ≥10%: 60.0% vs 36.2% vs 16.1%; P < .001) than BiVP or LVSP. CONCLUSION: LBBP yielded long-term clinical outcomes superior to those of BiVP and LVSP. The role of LVSP for CRT needs to be reevaluated because of its high mortality risk.
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Terapia de Resincronización Cardíaca , Insuficiencia Cardíaca , Humanos , Masculino , Femenino , Terapia de Resincronización Cardíaca/métodos , Anciano , Insuficiencia Cardíaca/terapia , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/mortalidad , Resultado del Tratamiento , Ecocardiografía , Fascículo Atrioventricular/fisiopatología , Volumen Sistólico/fisiología , Tabique Interventricular/fisiopatología , Estudios Prospectivos , Estudios de Seguimiento , Función Ventricular Izquierda/fisiología , Persona de Mediana Edad , Bloqueo de Rama/terapia , Bloqueo de Rama/fisiopatología , Factores de Tiempo , Remodelación Ventricular/fisiologíaRESUMEN
BACKGROUND: In performing left bundle branch pacing (LBBP), various QRS morphologies are observed as the lead penetrates the ventricular septum (VS). This study aimed to evaluate these characteristics and infer the mechanism underlying each QRS morphology. METHODS: In 19 patients who met the strict criteria for LBB capture, we classified the QRS morphologies observed during the LBBP procedure into seven patterns, the first five of which were determined by the depth of penetration: right ventricular septal pacing (RVSP), intraventricular septal pacing (IVSP1 and IVSP2), endocardial side of left ventricular septal pacing (LVSeP), nonselective LBBP (NS-LBBP), selective LBBP (S-LBBP), and NS-LBBP with anodal capture. The parameters of the QRS morphologies in these seven patterns were evaluated. RESULTS: Among the first five patterns, stimulus-QRSend duration (s-QRSend) was the narrowest in IVSP1 rather than in NS-LBBP, and stimulus-to-peak of R wave in V6 (s-LVAT) was significantly shortened in two steps, from RVSP to IVSP1 (96 ± 11; 82 ± 8 ms, p < .01) and from LVSeP to NS-LBBP (76 ± 7; 60 ± 4 ms, p < .01). The late-R duration in V1 was significantly prolonged in the order of LVSeP, NS-LBBP, and S-LBBP (45 ± 7; 53 ± 10; 71 ± 15 ms, respectively, p < .01). CONCLUSIONS: s-QRSend was the narrowest in IVSP1 rather than in NS-LBBP among the QRS morphologies observed during lead penetration through the VS. The prolonged late-R duration in V1 and abrupt shortening of the s-LVAT in V6 may help determine LBB capture during lead penetration.
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Bloqueo de Rama/fisiopatología , Estimulación Cardíaca Artificial/métodos , Electrodos Implantados , Tabique Interventricular/fisiopatología , Anciano , Electrocardiografía , Femenino , Humanos , MasculinoRESUMEN
CONTEXT: Lipodystrophy syndromes are rare disorders of deficient adipose tissue, low leptin, and severe metabolic disease, affecting all adipose depots (generalized lipodystrophy, GLD) or only some (partial lipodystrophy, PLD). Left ventricular (LV) hypertrophy is common (especially in GLD); mechanisms may include hyperglycemia, dyslipidemia, or hyperinsulinemia. OBJECTIVE: Determine effects of recombinant leptin (metreleptin) on cardiac structure and function in lipodystrophy. METHODS: Open-label treatment study of 38 subjects (18 GLD, 20 PLD) at the National Institutes of Health before and after 1 (Nâ =â 27), and 3 to 5 years (Nâ =â 23) of metreleptin. Outcomes were echocardiograms, blood pressure (BP), triglycerides, A1c, and homeostasis model assessment of insulin resistance. RESULTS: In GLD, metreleptin lowered triglycerides (median [interquartile range] 740 [403-1239], 138 [88-196], 211 [136-558] mg/dL at baseline, 1 year, 3-5 years, Pâ <â .0001), A1c (9.5â ±â 3.0, 6.5â ±â 1.6, 6.5â ±â 1.9%, Pâ <â .001), and HOMA-IR (34.1 [15.2-43.5], 8.7 [2.4-16.0], 8.9 [2.1-16.4], Pâ <â .001). Only HOMA-IR improved in PLD (Pâ <â .01). Systolic BP decreased in GLD but not PLD. Metreleptin improved cardiac parameters in patients with GLD, including reduced posterior wall thickness (9.8â ±â 1.7, 9.1â ±â 1.3, 8.3â ±â 1.7 mm, Pâ <â .01), and LV mass (140.7â ±â 45.9, 128.7â ±â 37.9, 110.9â ±â 29.1 g, Pâ <â .01), and increased septal e' velocity (8.6â ±â 1.7, 10.0â ±â 2.1, 10.7â ±â 2.4 cm/s, Pâ <â .01). Changes remained significant after adjustment for BP. In GLD, multivariate models suggested that reduced posterior wall thickness and LV mass index correlated with reduced triglycerides and increased septal e' velocity correlated with reduced A1c. No changes in echocardiographic parameters were seen in PLD. CONCLUSION: Metreleptin attenuated cardiac hypertrophy and improved septal e' velocity in GLD, which may be mediated by reduced lipotoxicity and glucose toxicity. The applicability of these findings to leptin-sufficient populations remains to be determined.
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Cardiomegalia/prevención & control , Hipertrofia Ventricular Izquierda/prevención & control , Leptina/análogos & derivados , Lipodistrofia/complicaciones , Lipodistrofia/tratamiento farmacológico , Adolescente , Adulto , Presión Sanguínea , Cardiomegalia/etiología , Ecocardiografía , Femenino , Hemoglobina Glucada/análisis , Humanos , Hipertrofia Ventricular Izquierda/patología , Hipertrofia Ventricular Izquierda/fisiopatología , Resistencia a la Insulina , Leptina/uso terapéutico , Lipodistrofia/patología , Lipodistrofia Generalizada Congénita/complicaciones , Lipodistrofia Generalizada Congénita/dietoterapia , Masculino , Persona de Mediana Edad , National Institutes of Health (U.S.) , Estudios Prospectivos , Triglicéridos/sangre , Estados Unidos , Tabique Interventricular/patología , Tabique Interventricular/fisiopatología , Adulto JovenRESUMEN
BACKGROUND: Nonselective His-bundle pacing (nsHBp), nonselective left bundle branch pacing (nsLBBp), and left ventricular septal myocardial pacing (LVSP) are recognized as physiological pacing techniques. OBJECTIVE: The purpose of this study was to compare differences in ventricular depolarization between these techniques using ultra-high-frequency electrocardiography (UHF-ECG). METHODS: In patients with bradycardia, nsHBp, nsLBBp (confirmed concomitant left bundle branch [LBB] and myocardial capture), and LVSP (pacing in left ventricular [LV] septal position without proven LBB capture) were performed. Timings of ventricular activations in precordial leads were displayed using UHF-ECG, and electrical dyssynchrony (e-DYS) was calculated as the difference between the first and last activation. Duration of local depolarization (Vd) was determined as width of the UHF-QRS complex at 50% of its amplitude. RESULTS: In 68 patients, data were collected during nsLBBp (35), LVSP (96), and nsHBp (55). nsLBBp resulted in larger e-DYS than did LVSP and nsHBp [- 24 ms (-28;-19) vs -12 ms (-16;-9) vs 10 ms (7;14), respectively; P <.001]. nsLBBp produced similar values of Vd in leads V5-V8 (36-43 ms vs 38-43 ms; P = NS in all leads) but longer Vd in leads V1-V4 (47-59 ms vs 41-44 ms; P <.05) as nsHBp. LVSP caused prolonged Vd in leads V1-V8 compared to nsHBp and longer Vd in leads V5-V8 compared to nsLBBp (44-51 ms vs 36-43 ms; P <.05) regardless of R-wave peak time in lead V5 or QRS morphology in lead V1 present during LVSP. CONCLUSION: nslbbp preserves physiological LV depolarization but increases interventricular electrical dyssynchrony. LV lateral wall depolarization during LVSP is prolonged, but interventricular synchrony is preserved.
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Fascículo Atrioventricular/fisiopatología , Bloqueo de Rama/terapia , Estimulación Cardíaca Artificial/métodos , Electrocardiografía/métodos , Ventrículos Cardíacos/fisiopatología , Función Ventricular Izquierda/fisiología , Tabique Interventricular/fisiopatología , Anciano , Bloqueo de Rama/fisiopatología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Estudios ProspectivosRESUMEN
Left bundle branch pacing (LBBP) has been adopted as a new pacing therapy whether in routine pacing or patients with heart failure, but the criteria for a completely captured LBBP are too complicated and have a low success rate in routine clinical practice.Consecutive patients with pacing therapy indications were enrolled. Left bundle branch area pacing (LBBAP) was conducted, and the presence of LBB potential, paced QRS duration, stimulus to left ventricular activation time (Stim-LVAT), and LBB potential to left ventricular activation time (LBB po-LVAT) were determined and utilized to characterize LBBAP modalities. Pacing parameters and safety were assessed at 6-month follow-up. LBBAP succeeded in 95.6% of patients (103/106) who completed the 6-month follow-up. Complete LBBP was achieved in 21 (20%) patients, characterized with a short Stim-LVAT equal to LBB po-LVAT. Incomplete LBBP was achieved in 58 (56%) patients with a short Stim-LVAT equal to LBB po-LVAT at a high pacing output and a relatively longer Stim-LVAT at a low pacing output. Deep septal pacing (DSP) characterized with no LBB potential and a longer Stim-LVAT (83.3 ± 7.7 ms) than that in LBBP (71.37 ± 7.1 ms, P < 0.01 versus DSP) was observed in 24 (23%) patients. Complete LBBP had a longer total procedure time and longer fluoroscopic time than the other two groups.This study describes the similarities and differences in electrophysiological characteristics and the possible mechanisms of the different types of LBBAP, classified into 3 modalities in routine clinical practice, each with narrow paced QRS duration and stable parameters, indicating LBBAP can be a near-physiological pacing modality.
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Bloqueo de Rama/terapia , Estimulación Cardíaca Artificial/métodos , Sistema de Conducción Cardíaco/fisiopatología , Insuficiencia Cardíaca/terapia , Anciano , Anciano de 80 o más Años , Bloqueo de Rama/fisiopatología , Electrofisiología Cardíaca/métodos , Ecocardiografía/métodos , Electrocardiografía/métodos , Fenómenos Electrofisiológicos , Femenino , Estudios de Seguimiento , Insuficiencia Cardíaca/fisiopatología , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Estudios Prospectivos , Tabique Interventricular/fisiopatologíaRESUMEN
OBJECTIVES: Little is known about cardiac hemodynamics in the fetus with transposition of the great arteries and intact ventricular septum (TGA-IVS). Better understanding of the fetal physiology in TGA-IVS would help to provide insights into specific clinical complications observed after birth, in particular neonatal hypoxia and pulmonary hypertension. The aim of this study was to assess cardiac hemodynamics in fetuses with TGA-IVS by performing systematic longitudinal echocardiographic follow-up from diagnosis to delivery. METHODS: This was a longitudinal retrospective study of fetuses referred between 2010 and 2018 to the Sainte-Justine University Hospital Centre. Complete assessment of cardiac hemodynamics was performed in fetuses with TGA-IVS at 18-22, 28-32 and 35-38 weeks' gestation, which were compared with normal fetuses matched for gestational age. The maximum diameter of the foramen ovale was measured using two-dimensional echocardiography under the guidance of color Doppler echocardiography. Fetal cardiac hemodynamics were analyzed according to postnatal preductal transcutaneous oxygen saturation (TcSO2 ) < 65% or ≥ 65%, as a neonatal outcome, in fetuses with TGA-IVS. RESULTS: In total, 59 fetuses with TGA-IVS and 160 normal fetuses were included. Global cardiac output was significantly higher in fetuses with TGA-IVS than in controls, mainly owing to higher global pulmonary output, while global systemic cardiac output did not differ between TGA-IVS fetuses and controls throughout pregnancy. Aortic flow (right ventricular output in fetuses with TGA-IVS, left ventricular output in controls) was significantly higher in fetuses with TGA-IVS than in normal fetuses. Ductal flow was significantly lower in fetuses with TGA-IVS at every timepoint, and this difference increased considerably after 28-32 weeks. In parallel, the diameter of the foramen ovale was significantly smaller in fetuses with TGA-IVS at 28-32 and 35-38 weeks, with a stagnation in growth after 28 weeks, compared with continuous growth in normal fetuses. Most of these cardiac hemodynamic anomalies in fetuses with TGA-IVS were already present at 18-22 weeks, and the differences became greater at 28-32 weeks' gestation. TGA-IVS neonates with TcSO2 < 65% had lower fetal left ventricular output, higher diastolic ductal retrograde flow and smaller foramen ovale at 28-32 weeks, compared with fetal values in those with postnatal TcSO2 ≥ 65%. CONCLUSIONS: Compared with normal fetuses, those with TGA-IVS undergo a complex redistribution of blood flow during the second half of pregnancy, with higher global pulmonary flow, lower ductal flow (with negative diastolic flow at the end of pregnancy) and a smaller foramen ovale. In addition, fetal cardiac hemodynamic anomalies observed at 28-32 weeks' gestation were associated with lower postnatal TcSO2 . These observations may provide a better understanding of premature closure of the foramen ovale and postnatal hypoxia that are specific to TGA-IVS physiology. © 2019 International Society of Ultrasound in Obstetrics and Gynecology.
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Foramen Oval/anomalías , Transposición de los Grandes Vasos/diagnóstico por imagen , Tabique Interventricular/diagnóstico por imagen , Gasto Cardíaco , Estudios de Cohortes , Ecocardiografía Doppler en Color , Femenino , Foramen Oval/diagnóstico por imagen , Cardiopatías Congénitas/diagnóstico por imagen , Cardiopatías Congénitas/fisiopatología , Humanos , Estudios Longitudinales , Embarazo , Estudios Retrospectivos , Transposición de los Grandes Vasos/fisiopatología , Tabique Interventricular/fisiopatologíaRESUMEN
BACKGROUND: Bronchopulmonary dysplasia (BPD) associated with pulmonary hypertension (PH) is a significant source of morbidity and mortality in premature infants. Recent advances have allowed the use of cardiovascular magnetic resonance (CMR) in the assessment of respiratory and cardiac disease in infants with BPD. In adults and older pediatric patients, decreased CMR interventricular septal curvature correlates with increased mean pulmonary artery pressure and pulmonary vascular resistance. The current study sought to determine the relationship of CMR derived septal curvature in neonates with BPD and BPD-PH with a need for PH therapy. METHODS: Forty moderate or severe BPD and 12 mild BPD or control infants were imaged without contrast between 38 and 47 weeks post-menstrual age on a neonatal-sized, neonatal intensive care unit-sited 1.5 T CMR scanner. CMR indices including eccentricity index (CMR-EI) and septal curvature were measured and compared to BPD severity and clinical outcomes including hospital length of stay (LOS), duration of respiratory support, respiratory support level at discharge and PH therapy. RESULTS: CMR-EI was directly associated and septal curvature was inversely associated with BPD severity. In a univariate analysis, CMR-EI and septal curvature were associated with increased hospital LOS, duration of respiratory support, respiratory support at hospital discharge, and need for PH therapy. In multivariable analysis CMR-EI was associated with hospital LOS and duration of respiratory support and septal curvature was associated with respiratory support at hospital discharge. Septal curvature was the only clinical or CMR variable associated with need for PH therapy (R2 = 0.66, p = 0.0014) in multivariable analysis demonstrating improved discrimination beyond CMR-EI. CONCLUSIONS: CMR derived septal curvature correlates significantly with clinical outcomes including hospital LOS, duration of respiratory support, respiratory support level at hospital discharge, and PH therapy in neonates with BPD and BPD-PH. Further, CMR derived septal curvature demonstrated improved discrimination of need for PH therapy and respiratory support at discharge compared to clinical variables and other CMR indices, supporting septal curvature as a non-invasive marker of PH in this population with potential to guide management strategies.
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Presión Arterial , Displasia Broncopulmonar/diagnóstico por imagen , Hipertensión Pulmonar/diagnóstico por imagen , Imagen por Resonancia Cinemagnética , Arteria Pulmonar/fisiopatología , Resistencia Vascular , Tabique Interventricular/diagnóstico por imagen , Antihipertensivos/uso terapéutico , Presión Arterial/efectos de los fármacos , Displasia Broncopulmonar/complicaciones , Displasia Broncopulmonar/fisiopatología , Displasia Broncopulmonar/terapia , Femenino , Humanos , Hipertensión Pulmonar/etiología , Hipertensión Pulmonar/fisiopatología , Hipertensión Pulmonar/terapia , Recién Nacido , Tiempo de Internación , Masculino , Valor Predictivo de las Pruebas , Arteria Pulmonar/efectos de los fármacos , Terapia Respiratoria , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Factores de Tiempo , Resultado del Tratamiento , Resistencia Vascular/efectos de los fármacos , Tabique Interventricular/efectos de los fármacos , Tabique Interventricular/fisiopatologíaRESUMEN
BACKGROUND: Interest has grown in recent years in bipolar radiofrequency ablation (B-RFA). However, indications and outcome in patients with ventricular tachycardia (VT) are still to be defined. OBJECTIVE: The purpose of this study was to describe patient selection, safety and effectiveness of B-RFA, in a pilot cohort study of patients with nonischemic dilated cardiomyopathy (NIDCM) and drug-refractory VT. METHODS: We enrolled 21 patients with NIDCM (mean age 66±10 years; 18/21 (86%) men; left ventricular ejection fraction 35%±14%; 100% redo procedures) scheduled for a B-RFA procedure because of drug-refractory VT of suspected septal (interventricular septum [IVS]) origin. After electroanatomic mapping by using the CARTO®3 system, B-RFA was performed in all patients. Short- and long-term outcomes, including procedural success, major complications, and occurrence of major ventricular arrhythmias (MVAs), were evaluated at 25±8 months of follow-up (FU). RESULTS: Endocardial mapping showed IVS scar in all patients and extra-IVS in 7 patients (33%). B-RFA was performed at an average power of 33 W, for 60-90 seconds, over a 4.1 cm2 area, with 13±3 mm distance between catheters tips. The impedance drop was 27±4 Ω. The primary end point of noninducibility of the target clinical VT was obtained in 20 patients (95%). During FU, MVAs were documented in 7 patients (33%). FU MVAs occurred in all (100%) patients with extra-IVS localizations (7 of 7) or inflammatory nonischemic cardiomyopathy etiology (2 of 2). IVS thinning (tip-to-tip catheter distance < 5 mm) represented the only anatomical limitation to B-RFA. CONCLUSION: B-RFA is feasible in patients with NIDCM and drug-refractory VT of septal origin. Extra-IVS substrate and inflammatory NIDCM etiology were associated with an adverse outcome.
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Ablación por Catéter/métodos , Sistema de Conducción Cardíaco/fisiopatología , Taquicardia Ventricular/cirugía , Función Ventricular Izquierda/fisiología , Tabique Interventricular/fisiopatología , Anciano , Mapeo Epicárdico , Femenino , Estudios de Seguimiento , Humanos , Masculino , Proyectos Piloto , Estudios Prospectivos , Taquicardia Ventricular/fisiopatología , Resultado del TratamientoRESUMEN
Managing arrhythmias from the left ventricular summit and interventricular septum is a major challenge for the clinical electrophysiologist requiring intimate knowledge of cardiac anatomy, advanced training and expertise. Novel mapping and ablation strategies are needed to treat arrhythmias originating from these regions given the current suboptimal long-term success rates with standard techniques. Herein, we describe innovative approaches to improve acute and long-term clinical outcomes such as mapping and ablation using the septal coronary venous system and the septal coronary arteries, alcohol ablation, coil embolization, and ablation of all early sites among others.
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Ablación por Catéter/métodos , Técnicas Electrofisiológicas Cardíacas , Taquicardia Ventricular/fisiopatología , Tabique Interventricular/fisiopatología , Ventrículos Cardíacos/fisiopatología , Humanos , Taquicardia Ventricular/diagnóstico , Tomografía Computarizada por Rayos X , Tabique Interventricular/diagnóstico por imagenRESUMEN
Basal septal hypertrophy (BSH) is commonly seen in patients with systemic hypertension and has been associated with increased afterload. The impact of localized hypertrophy on left ventricular (LV) and left atrial (LA) function is still unclear. Our aim is to investigate if BSH is a marker of a more pronounced impact of hypertension on cardiac function in the early stages of hypertensive heart disease. An echocardiogram was performed in 163 well-controlled hypertensive patients and 22 healthy individuals. BSH was defined by a basal-to-mid septal thickness ratio ≥1.4. LV dimensions and mass were evaluated. LV global and regional deformation was assessed by 2-dimensional (2D) speckle tracking echocardiography, and LV diastolic function by 2D and Doppler imaging. LA function was evaluated with phasic volume indices calculated from 2D and 3-dimensional volumes, as well as speckle tracking echocardiography. The population was 54% men, mean age 57 (53 to 60) years. BSH was seen in 20% (nâ¯=â¯32) of the hypertensive cohort. Patients with BSH showed decreased regional LV systolic deformation, impaired LV relaxation with a higher proportion of indeterminate LV diastolic function, and LA functional impairment defined by a reduction of reservoir strain and a change in LA functional dynamics. In conclusion, in well-controlled hypertension impairment of LV and LA function is present in patients with early LV remodeling and localized hypertrophy. BSH might be useful as an early marker of the burden of hypertensive heart disease.
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Cardiomegalia/etiología , Hipertensión/complicaciones , Tabique Interventricular/patología , Función del Atrio Izquierdo , Cardiomegalia/diagnóstico por imagen , Cardiomegalia/fisiopatología , Estudios de Cohortes , Ecocardiografía , Femenino , Humanos , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Función Ventricular Izquierda , Tabique Interventricular/diagnóstico por imagen , Tabique Interventricular/fisiopatologíaRESUMEN
PURPOSE: Paroxysmal Permeability Disorders (PPDs) comprise a variety of diseases characterized by recurrent and transitory increase of endothelial permeability. Idiopathic Systemic Capillary Leak Syndrome (ISCLS) is a rare PPD that leads to an abrupt massive shift of fluids and proteins from the intravascular to the interstitial compartment. In some cases, tissue edema may involve the myocardium, but its role in the development of shock has not been elucidated so far. MATERIALS AND METHODS: Assessment of cardiac involvement during ten life-threatening ISCLS episodes admitted to ICU. RESULTS: Transthoracic echocardiographic examination was performed in eight episodes, whereas a poor acoustic window prevented cardiac ultrasound assessment in two episodes. Myocardial edema was detected by echocardiography in eight episodes and marked pericardial effusion in one-episode. Cardiac magnetic resonance showed diffuse myocardial edema in another episode. In one case, myocardial edema caused fulminant left ventricular dysfunction, which required extracorporeal life support. The mean septum thickness was higher during the shock phase compared to the recovery phase [15.5 mm (13.1-21 mm) vs. 9.9 mm (9-11.3 mm), p = .0003]. Myocardial edema resolved within 72 h. CONCLUSIONS: During early phases of ISCLS, myocardial edema commonly occurs and can induce transient myocardial dysfunction, potentially contributing to the pathogenesis of shock.
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Síndrome de Fuga Capilar/complicaciones , Edema/complicaciones , Choque/complicaciones , Acústica , Adulto , Síndrome de Fuga Capilar/diagnóstico por imagen , Cardiomiopatías/complicaciones , Cardiomiopatías/diagnóstico por imagen , Comorbilidad , Edema/diagnóstico por imagen , Oxigenación por Membrana Extracorpórea/efectos adversos , Corazón/fisiopatología , Hemodinámica , Humanos , Inflamación , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Permeabilidad , Choque/diagnóstico por imagen , Ultrasonografía , Disfunción Ventricular Izquierda/fisiopatología , Tabique Interventricular/fisiopatologíaRESUMEN
BACKGROUND: Cardiac conduction disturbance (CD) is the most frequent complication following transcatheter aortic valve replacement (TAVR). This study examined whether the anatomy of the membranous septum (MS) could provide useful information about the risk of CD following TAVR with a balloon-expandable valve (BEV).MethodsâandâResults:Among 132 consecutive patients, 106 (mean age, 85.6±5.1 years; 75 females) were included in the study. Using preoperative CT and angiography, MS length and implantation depth (ID) were assessed. The MS length minus the prosthesis ID was calculated (∆MSID). Correlation between CD, defined as new-onset left-bundle branch block (LBBB) or the need for permanent pacemaker (PPM) within 1 week after the procedure, and MS length were evaluated. A total of 19 patients (18%) developed CD following TAVR. MS length was significantly shorter in these patients than in those without CD (5.3±1.3 vs. 6.6±1.4; P<0.001), and was the important predictor of CD (odds ratio [OR]: 0.43, 95% confidence interval [CI]: 0.27-0.69, P<0.001). When considering the pre- and postprocedural parameters, the ∆MSID was smaller in patients with CD (-1.7±1.5 vs. 0.8±1.9, P<0.001), and emerged as the important predictor of CD (OR: 0.47, 95% CI: 0.33-0.69, P<0.001). CONCLUSIONS: Short MS is associated with an increased risk of CD after TAVR with BEV.
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Estenosis de la Válvula Aórtica/cirugía , Valvuloplastia con Balón/efectos adversos , Bloqueo de Rama/etiología , Angiografía por Tomografía Computarizada , Prótesis Valvulares Cardíacas , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Reemplazo de la Válvula Aórtica Transcatéter/instrumentación , Tabique Interventricular/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/fisiopatología , Bloqueo de Rama/diagnóstico , Bloqueo de Rama/fisiopatología , Femenino , Humanos , Masculino , Valor Predictivo de las Pruebas , Diseño de Prótesis , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Índice de Severidad de la Enfermedad , Factores de Tiempo , Resultado del Tratamiento , Tabique Interventricular/fisiopatologíaRESUMEN
INTRODUCTION: Permanent deep septal stimulation with capture of the left bundle branch (LBB) enables maintenance/restoration of the physiological activation of the left ventricle. However, it is almost always accompanied by the simultaneous engagement of the local septal myocardium, resulting in a fused (nonselective) QRS complex, therefore, confirmation of LBB capture remains difficult. METHODS: We hypothesized that programmed extrastimulus technique can differentiate nonselective LBB capture from myocardial-only capture as the effective refractory period (ERP) of the myocardium is different from the ERP of the LBB. Consecutive patients undergoing pacemaker implantation underwent programmed stimulation delivered from the lead implanted in a deep septal position. Responses to programmed stimulation were categorized on the basis of sudden change in the QRS morphology of the extrastimuli, observed when ERP of LBB or myocardium was encroached upon, as: "myocardial," "selective LBB," or nondiagnostic (unequivocal change of QRS morphology). RESULTS: Programmed deep septal stimulation was performed 269 times in 143 patients; in every patient with the use of a basic drive train of 600 milliseconds and in 126 patients also during intrinsic rhythm. The average septal-myocardial refractory period was shorter than the LBB refractory period: 263.0 ± 34.4 vs 318.0 ± 37.4 milliseconds. Responses diagnostic for LBB capture ("myocardial" or "selective LBB") were observed in 114 (79.7%) of patients. CONCLUSIONS: A novel maneuver for the confirmation of LBB capture during deep septal stimulation was developed and found to enable definitive diagnosis by visualization of both components of the paced QRS complex: selective paced LBB QRS and myocardial-only paced QRS.
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Potenciales de Acción , Arritmias Cardíacas/terapia , Fascículo Atrioventricular/fisiopatología , Estimulación Cardíaca Artificial , Técnicas Electrofisiológicas Cardíacas , Insuficiencia Cardíaca/terapia , Frecuencia Cardíaca , Marcapaso Artificial , Tabique Interventricular/fisiopatología , Anciano , Anciano de 80 o más Años , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatología , Femenino , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Periodo Refractario Electrofisiológico , Factores de Tiempo , Resultado del TratamientoRESUMEN
Percutaneous transluminal septal myocardial ablation (PTSMA) has become a significant treatment for symptomatic patients with hypertrophic obstructive cardiomyopathy (HOCM) despite maximal medical therapy. The target septal arteries usually arise from the left anterior descending artery (LAD). However, when septal perforators do not originate from the LAD, non-LAD septal perforators should be included as candidate-target septal branches that feed the hypertrophic septal myocardium, causing left ventricular outflow tract (LVOT) obstruction. Data pertaining to the procedure remain limited. We aimed to investigate PTSMA through the non-LAD septal perforators in patients with HOCM. In this case series review, we evaluated the baseline characteristics, echocardiographic features, and angiographic features, as well as symptoms and pressure gradient before and after PTSMA through the non-LAD septal perforators. Among 202 consecutive patients who underwent PTSMA for HOCM with LVOT obstruction, 21 had non-LAD septal branches that fed the hypertrophic septal myocardium and received alcohol ablation. Non-LAD septal perforators could be used as an alternative route for PTSMA in patients who experienced ineffective ablation of the septal branch that arises from the LAD. This unique procedure may improve response rates and overall outcomes of patients with HOCM.
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Técnicas de Ablación , Cardiomiopatía Hipertrófica/cirugía , Etanol/administración & dosificación , Obstrucción del Flujo Ventricular Externo/cirugía , Tabique Interventricular/cirugía , Técnicas de Ablación/efectos adversos , Anciano , Anciano de 80 o más Años , Cardiomiopatía Hipertrófica/diagnóstico por imagen , Cardiomiopatía Hipertrófica/fisiopatología , Bases de Datos Factuales , Etanol/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recuperación de la Función , Sistema de Registros , Estudios Retrospectivos , Resultado del Tratamiento , Función Ventricular Izquierda , Obstrucción del Flujo Ventricular Externo/diagnóstico por imagen , Obstrucción del Flujo Ventricular Externo/fisiopatología , Tabique Interventricular/diagnóstico por imagen , Tabique Interventricular/fisiopatologíaRESUMEN
INTRODUCTION: There is a surge of interest in alternate site pacing to prevent pacing-induced left ventricular dysfunction. However, little is known regarding the appropriate atrioventricular (AV) delay between right ventricular (RV) septal and RV apical pacing for optimal hemodynamic benefit. OBJECTIVES: To determine the programmed values of atrial sensed and atrial paced AV delays in basal RV septal and apical RV pacing that results in the maximum delivered stroke volume (SV). METHODS: We calculated the Doppler-derived SV at various sensed and paced AV delays in 50 patients with complete AV block implanted with a dual-chamber pacemaker (group A: 25 RV apical pacing; group B: 25 RV septal pacing). The hemodynamic difference in terms of the SV between sensed and paced AV delay, corresponding to the site of RV pacing was then compared for statistical significance. RESULTS: In group A, maximal SV was derived at a sensed AV delay of 123.2 ± 11 ms and paced AV delay of 129.2 ± 10 ms, and in group B, at a sensed AV delay of 123.6 ± 8 ms and paced AV delay of and 132.8 ± 7 ms. At these intervals, there was no difference in the SV between septal and apical RV pacing (P = .28 and .22, respectively). CONCLUSION: The atrial sensed and atrial paced AV delays for septal and apical RV pacing for optimal hemodynamics are similar. For optimal hemodynamics, the atrial paced AV delay is longer than the atrial sensed AV delay.