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1.
J Electrocardiol ; 87: 153790, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39232409

RESUMEN

BACKGROUND: Long QT syndrome (LQTS) is a genetic cardiac disease, where the corrected QT (QTc) interval is prolonged. It can cause arrhythmias and lead to a sudden cardiac death. Duration of the QT interval depends on the heart rate and this dependency is treated with QT correction. However, the current QT correction methods have well known problems and limitations. OBJECTIVE: We study the relevance of QT correction method in evaluating the risk of LQTS. We evaluate the reliability of the present and recently developed QT correction methods to discriminate LQTS subjects from healthy controls. METHODS: We use the clinically prevalent QT correction methods, particularly Bazett and Fridericia, in comparison with the recently developed AccuQT method. The data of healthy controls and LQTS subjects is extracted from the Rochester THEW database. The analysis accounts for sex, major LQTS subtypes, and beta-blocker treatment. RESULTS: QT values corrected with AccuQT discriminate the healthy and LQTS samples with the best accuracy, leading to (TP, TN) = (0.87, 0.65) with the conventional 450 ms threshold for LQTS. Fridericia correction yields lower sensitivity (0.71), but comparable balanced accuracy, whereas Bazett shows significantly less accurate results due to overcorrection at lower heart rates. CONCLUSION: The selected QT correction method is important in the identification of LQTS. In particular, the use of Bazett correction should be questioned. Fridericia correction yields good results with respect to its simplicity. AccuQT has the best accuracy out of all the methods for LQTS discrimination. For practical applicability, however, AccuQT needs further validation in realistic clinical conditions.

2.
Int J Cancer ; 2024 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-39244732

RESUMEN

An example of chemotherapy-induced cardiotoxicity in cancer survivors is acquired long QT syndrome (aLQTS), which may cause serious yet preventable life-threatening consequences. Our objective was to identify and characterize childhood acute lymphoblastic leukemia (ALL) survivors with possible aLQTS using maximal exercise testing. In this cross-sectional study with exploratory analysis, a total of 250 childhood ALL survivors were evaluated for abnormal QT interval prolongation using the McMaster cycle exercise test. A total of 198 survivors (102 males; 96 females), having reached their V ̇ O 2 $$ \dot{\mathrm{V}}{\mathrm{O}}_2 $$ peak (mean 32.1 ± 8.4 mL/kg/min; range 15.5-57.8 mL/kg/min), were included in our analyses. Two survivors were excluded for possible congenital LQTS. QT intervals were corrected for heart rate using the Bazett, Fridericia, and Rautaharju formulas at rest (supine, sitting, and standing positions), at the end of each stage of the CPET, and at 1, 3, and 5 minutes into the recovery period. The corrected QT (QTc) of borderline (n = 37) and long QT survivors (n = 20) was significantly longer than normal survivors (n = 141) at rest, exercise, and recovery. Out of 57 survivors presenting an abnormal QTc prolongation, 40 survivors (70%) showed no QT interval anomalies at rest but developed various anomalies during exercise. No significant differences were found between the groups for any of the measured clinical characteristics or cardiac parameters. The standardization of exercise testing in the regular follow-up of oncology patients is necessary for appropriate cardiac prevention and surveillance to enhance the health and quality of life of the ever-increasing number of cancer survivors.

3.
Front Cardiovasc Med ; 11: 1423647, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39267801

RESUMEN

Background: Osimertinib is a third-generation epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor that has become the first-line treatment for non-small cell lung cancer harboring EGFR mutations, with the potential risk of QT prolongation and heart failure. However, few cases have reported malignant ventricular arrhythmias. Here, we report a case of recurrent ventricular fibrillation (VF) and Torsade de Pointes (TdP) secondary to QT prolongation and heart failure induced by osimertinib. Case summary: A 70-year-old woman presented with chest tightness and dyspnea for 1 week and ventricular fibrillation upon admission, with a medical history of lung adenocarcinoma harboring an EGFR exon 21 p.L858R mutation. She was under osimertinib for 3 months. Electrocardiography after defibrillation suggested QTc prolongation (655 ms) and T wave alternans. Ultrasound cardiography displayed left ventricular ejection fraction (LVEF) of 29% and severe mitral regurgitation. Laboratory tests indicated elevated N-terminal pro-B-type natriuretic peptide and hypokalemia. Genetic testing suggested no pathogenic mutations. We considered acquired long QT syndrome and heart failure with reduced ejection fraction induced by osimertinib as the chief causes of ventricular arrhythmia and hypokalemia as an important trigger. Despite intubation, sedation, and the administration intravenous magnesium and potassium and lidocaine, the patient presented with recurrent TdP, which was managed by a low dose of isoproterenol (ISO, 0.17 ug/min). An implantable cardioverter defibrillator was declined. The patient is surviving without any relapse, with QTc of 490 ms and LVEF of 42% after a 6-month follow up. Conclusion: Regular monitoring is required during osimertinib administration, considering the risk of life-threatening cardiac events, such as malignant arrhythmias and heart failure. ISO, with an individual dose and target heart rate, may be beneficial for terminating TdP during poor response to other therapies.

4.
Artículo en Inglés | MEDLINE | ID: mdl-39108109

RESUMEN

BACKGROUND: Patients with permanent hypoparathyroidism experience an impaired quality of life, due to acute and chronic complications that may affect several organs, with an increased risk of hospitalisation and death. Adequate and continuous replacement therapy with calcium and calcitriol is necessary to avoid symptoms and long-term complications related to hypocalcemia. CASE PRESENTATION: A 63 years old male, affected by permanent post-surgical hypoparathyroidism, was hospitalized in the cardiology department because of a dehiscence of the subcutaneous housing of the double-chambered implantable cardioverter-defibrillator. Chronic replacement therapy for hypoparathyroidism was poorly controlled and, during hospitalization, severe hypocalcemia occurred together with electrocardiographic and echocardiogram life-threatening alterations. CONCLUSION: Constant and targeted long-term replacement therapy with calcium and particularly calcitriol is necessary to avoid major consequences on patients' health, especially during acute events and in the presence of other comorbidities.

5.
Cureus ; 16(7): e63763, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39099957

RESUMEN

Atrial fibrillation (AF) is the most common long-term arrhythmia in adults. Rhythm control in patients with AF involves efforts to restore and maintain sinus rhythm and is accomplished by medication, catheter ablation, or electrical cardioversion. Amiodarone represents one of the most commonly used antiarrhythmic medications. Prolonged use of amiodarone can lead to many side effects. One of the most severe side effects is drug-induced long QT syndrome (LQTS), which can cause malignant arrhythmias and sudden cardiac death. We presented a case of a 52-year-old male who was admitted to the Coronary Unit due to first diagnosed AF with a rapid ventricular response. After amiodarone infusion was administrated the patient lost consciousness and the monitor displayed torsades de pointes (TdP) ventricular tachycardia with rapid conversion to ventricular fibrillation (VF). Cardiac resuscitation with two direct current (DC) shocks was performed. The patient was stabilized, and restoration of sinus rhythm with significant QT prolongation on the ECG was noted. This is a rare case of short-term amiodarone administration causing LQTS, TdP, and VF. The findings or observations emphasize the significance of diligent ECG monitoring during amiodarone treatment.

6.
Front Pharmacol ; 15: 1433663, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39188943

RESUMEN

Cardiotoxicity and QT interval prolongation have been a common cause of withdrawal of drugs from the market. FCN-437c is an oral, second-generation, potent, and selective CDK4/6 inhibitor for the treatment of patients with HR+/HER2- metastatic breast cancer. A single-center, double-blind, randomized, and placebo-controlled clinical study in healthy subjects was conducted to investigate the QTc prolongation potential of FCN-437c utilizing Concentration-QTc (C-QTc) modeling approach. FCN-437c was administered at doses of 300, and 400 mg with single oral administration, along with placebo, in 18 healthy subjects. Electrocardiograms (ECGs) through 24 h holter monitor and blood samples were collected. The Cmax of 400 mg single dose in healthy subjects is similar to that from therapeutic dose 200 mg QD at steady state in patients with cancer. The 90% CI upper limit of ΔΔQTcF at the Cmax geometric mean in both dose groups were <10 ms. It is concluded that FCN-437c has low risk of prolonging the QT interval at therapeutic dose. Systematic Review Registration: https://clinicaltrials.gov/study/NCT06290466?term=NCT06290466&rank=1, identifier [NCT06290466].

7.
J Pharmacol Sci ; 156(2): 134-141, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39179332

RESUMEN

Risperidone is a second-generation antipsychotic for treating schizophrenia and bipolar disorder. It can potently inhibit IKr, but is classified into conditional risk for torsade de pointes (TdP) by CredibleMeds®. Our previous studies using chronic atrioventricular block dogs showed that risperidone alone did not induce TdP, and that dl-sotalol (ß-adrenoceptor blockade plus IKr inhibition) induced TdP three times more frequently than d-sotalol (IKr inhibition alone). Since risperidone can block α1-adrenoceptor and decrease blood pressure, the resulting reflex-mediated increase of sympathetic tone on ß-adrenoceptor might protect the heart from its IKr inhibition-associated TdP. To validate this hypothesis, risperidone was administered to chronic atrioventricular block dogs after ß-adrenoceptor blocker atenolol infusion with monitoring J-Tpeak and Tpeak-Tend, which are proarrhythmic surrogate markers of "substrate" and "trigger" toward TdP, respectively. Atenolol alone induced TdP in 1 out of 5 dogs; moreover, an additional infusion of risperidone induced TdP in 3 out of 4 dogs. Risperidone prolonged QT interval, J-Tpeak and Tpeak-Tend in animals that induced TdP. These findings indicate that ß-adrenoceptor blockade can diminish repolarization reserve to augment risperidone's torsadogenic potential, thus advising caution when using ß-adrenoceptor blockers in patients with IKr inhibition-linked labile repolarization.


Asunto(s)
Antagonistas Adrenérgicos beta , Antipsicóticos , Atenolol , Risperidona , Torsades de Pointes , Risperidona/farmacología , Animales , Perros , Atenolol/farmacología , Antipsicóticos/farmacología , Antipsicóticos/efectos adversos , Antagonistas Adrenérgicos beta/farmacología , Torsades de Pointes/inducido químicamente , Bloqueo Atrioventricular/inducido químicamente , Masculino
8.
J Clin Anesth ; 98: 111574, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39121785

RESUMEN

STUDY OBJECTIVE: Although a prolonged heart rate-corrected QT interval (QTcI) is associated with an increased risk of mortality in the general population, its prognostic value in surgical patients remains unclear. We aimed to examine whether preoperative QTcI prolongation predicts short-term postoperative outcomes in elderly patients undergoing noncardiac surgery. DESIGN: The study was a retrospective analysis using the TriNetX network database. SETTING: Operating room. INTERVENTION: Assessment and categorization of preoperative QTcI. PATIENTS: Data of patients aged ≥65 years who underwent non-cardiac surgery between 2010 and 2023 were analyzed. MEASUREMENTS: Patients were categorized into four groups based on preoperative QTcI: long (500-600 ms), borderline (460-500 ms), high-normal (420-460 ms) and control (370-420 ms) groups. The groups were compared using a propensity score-matched analysis. The primary outcome was the all-cause 90-day mortality risk. The secondary outcomes included 90-day risks of postoperative new-onset atrial fibrillation (Af), ventricular arrhythmias (VAs), emergency visits, hospital readmissions, and pneumonia. RESULTS: In total, data on 519,929 patients were collected in this study. Pairwise comparisons showed that all QTcI prolongation groups demonstrated a heightened incidence of postoperative mortality, arrhythmias, and other complications compared to the control group. Patients with a long QTcI had a 3-fold higher risk of mortality (hazard ratio [HR] = 3.124, p < 0.001), Af (HR = 3.059, p < 0.001), and VAs (HR = 3.617, p < 0.001) than controls. The risks of emergency visits (HR = 1.287, p < 0.001), hospital readmissions (HR = 1.591, p < 0.001), and pneumonia (HR = 1.672, p < 0.001) were also higher in the long QTcI group than in the control group. A dose-dependent response was evident between QTcI and mortality as well as arrhythmia risk. CONCLUSION: Preoperative QTcI screening effectively risk-stratifies elderly surgical patients, with a QTcI≥500 ms being strongly predictive of short-term postoperative mortality and other complications. Incorporating QTcI assessment into the preoperative evaluation may guide perioperative monitoring and management.


Asunto(s)
Electrocardiografía , Síndrome de QT Prolongado , Complicaciones Posoperatorias , Humanos , Estudios Retrospectivos , Femenino , Anciano , Masculino , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/mortalidad , Síndrome de QT Prolongado/epidemiología , Anciano de 80 o más Años , Readmisión del Paciente/estadística & datos numéricos , Frecuencia Cardíaca , Periodo Preoperatorio , Arritmias Cardíacas/etiología , Arritmias Cardíacas/epidemiología , Arritmias Cardíacas/diagnóstico , Factores de Riesgo , Medición de Riesgo/métodos , Medición de Riesgo/estadística & datos numéricos , Fibrilación Atrial/diagnóstico , Incidencia , Pronóstico
9.
Sci Total Environ ; 953: 175791, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39216753

RESUMEN

This study delves into the relationship between environmental metal exposure and QT interval corrected for heart rate (QTc) prolongation, a critical marker for cardiovascular risk in the elderly. Although the interplay between metal exposure and QTc prolongation is important for predicting sudden cardiac death, it remains underexplored. Our analysis of 6478 participants from the Shenzhen aging-related disorder cohort involved measuring urinary concentrations of 22 trace metals and using mitochondrial DNA copy number (mtDNA-CN) as an indicator of mitochondrial dysfunction. Utilizing Bayesian kernel machine regression, and structural equation modeling, we assessed the effects of mixed trace metals on QTc prolongation. Our findings indicated a direct association between certain metals (Sb, Cu, Zn) and a 7 % increase in QTc prolongation risk, while Li, V, and Rb were associated with a 5 % reduction in risk. Elevated levels of V, Ti, and Cr corresponded to higher mtDNA-CN. Notably, restricted cubic splines revealed a U-shaped, nonlinear relationship between mtDNA-CN and QTc prolongation. After adjusting for metal exposure, an inverse correlation was observed between mtDNA-CN and QTc prolongation, suggesting mitochondrial dysfunction as a partial mediator.

10.
Pharmacol Res Perspect ; 12(4): e1249, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39017590

RESUMEN

This study assessed the pharmacokinetics (PKs) and pharmacodynamics (PDs) of two antihypertensive drugs, nifedipine and captopril, by exploring their main (blood pressure [BP]) and secondary effects (heart rate [HR] and QT interval [QT]) in spontaneously hypertensive rats. This study aimed to assess the relationship between PKs and PDs. Using these PD parameters, BP, HR, and QT during coadministration were estimated. The coadministration of nifedipine and captopril resulted in an increase in nifedipine's total body clearance (CLtot) and a reduction in its mean residence time (MRT) with an increase in the terminal elimination half-life (t1/2) and volume of distribution at steady state (Vdss) of captopril. However, no significant PK interactions were observed. During monotherapy, BP reduced rapidly following nifedipine infusion. Subsequently, despite the increase in nifedipine plasma concentration, BP recovered, likely because of homeostasis. Similar results were observed with coadministration. Subsequently, BP demonstrated a sustained reduction that was greater than or equal to the additive effect estimated from each PK. Captopril exhibited a minimal effect on HR, except for a transient increase observed immediately after starting infusion, consistent with observations during coadministration. Subsequently, the HR reduction was nearly equal to that calculated from the nifedipine PK. QT prolongation was more rapid with captopril than with nifedipine. Although QT prolongation during the initial 60 min of coadministration was approximately the sum of both effects, the recovery period to baseline QT was faster than that in the simulation.


Asunto(s)
Antihipertensivos , Presión Sanguínea , Captopril , Frecuencia Cardíaca , Hipertensión , Nifedipino , Ratas Endogámicas SHR , Captopril/farmacocinética , Captopril/administración & dosificación , Captopril/farmacología , Nifedipino/farmacocinética , Nifedipino/administración & dosificación , Nifedipino/farmacología , Animales , Antihipertensivos/farmacocinética , Antihipertensivos/administración & dosificación , Antihipertensivos/farmacología , Masculino , Ratas , Presión Sanguínea/efectos de los fármacos , Hipertensión/tratamiento farmacológico , Hipertensión/inducido químicamente , Frecuencia Cardíaca/efectos de los fármacos , Interacciones Farmacológicas , Semivida , Quimioterapia Combinada
11.
Front Physiol ; 15: 1346093, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39022307

RESUMEN

Introduction: Ventricular unloading during prolonged bed rest, mechanical circulatory support or microgravity has repeatedly been linked to potentially life-threatening arrhythmias. It is unresolved, whether this arrhythmic phenotype is caused by the reduction in cardiac workload or rather by underlying diseases or external stimuli. We hypothesized that the reduction in cardiac workload alone is sufficient to impair ventricular repolarization and to induce arrhythmias in hearts. Methods: Rat hearts were unloaded using the heterotopic heart transplantation. The ECG of unloaded and of control hearts were telemetrically recorded over 56 days resulting in >5 × 106 cardiac cycles in each heart. Long-term electrical remodeling was analyzed using a novel semi-automatic arrhythmia detection algorithm. Results: 56 days of unloading reduced left ventricular weight by approximately 50%. While unloading did not affect average HRs, it markedly prolonged the QT interval by approximately 66% and induced a median tenfold increase in the incidence of ventricular arrhythmias in comparison to control hearts. Conclusion: The current study provides direct evidence that the previously reported hypertrophic phenotype of repolarization during cardiac unloading translates into an impaired ventricular repolarization and ventricular arrhythmias in vivo. This supports the concept that the reduction in cardiac workload is a causal driver of the development of arrhythmias during ventricular unloading.

12.
Indian Heart J ; 2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39009079

RESUMEN

QT interval in an electrocardiogram (ECG) is interpreted after correction (QTc) by various formulas. This study aimed to compare the QTcs calculated by nine formulas. Sinus rhythm ECG reports of 1140 anonymous subjects showed uncorrected QT interval of 388.49 ± 42.74 ms. The QTc calculated by Bazett (443.96 ± 57.58 ms), Fridericia (424.37 ± 50.1 ms), Dmitrienko (433.59 ± 53.37 ms), Framingham (422.59 ± 45.55 ms), Schlamowitz (433.89 ± 48.05 ms), Hodges (421.6 ± 46.4 ms), Ashman (434.33 ± 54.05 ms), Rautaharju (427.75 ± 47.4 ms), and Sarma (429.22 ± 48.67 ms) showed a significant difference F (8, 10251) = 22.78 p < 0.0001. Hence, ECG should contain the formula for proper reporting and ease of interpretation by clinicians.

13.
Rev Cardiovasc Med ; 25(2): 64, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39077354

RESUMEN

Background: An example of a sodium-glucose cotransporter-2 (SGLT-2) inhibitor is Empagliflozin. It is a new medicine for treating type 2 diabetes mellitus (T2DM), but there is increasing interest in how empagliflozin affects the heart. This study aims to examine the impact of empagliflozin treatment on ventricular repolarization parameters in T2DM patients. Methods: T2DM patients were included in a prospective study. Measurements of ventricular repolarization parameters, including QT interval, corrected QT interval (QTc), QT dispersion (QTd), Tpeak-to-Tend interval (Tp-e), and Tpeak-to-Tend interval corrected for QTc (Tp-e/QTc), were obtained before initiating empagliflozin treatment and six months following treatment initiation. Statistical analysis was performed to assess changes in these parameters. Results: In this study, 95 patients were diagnosed with T2DM out of 177 patients. Among T2DM patients, 40 were male (42%) compared to 48% males in controls (p = 0.152). The average age of the T2DM patients was 60.2 ± 9.0 years, compared to 58.2 ± 9.2 years in the control group (p = 0.374). When comparing pre- and post-treatment measurements of parameters representing ventricular repolarization (QT 408.5 ± 22.9/378.8 ± 14.1, p < 0.001; QTc 427.0 ± 20.5/404.7 ± 13.8, p < 0.001; QTd 52.1 ± 1.2/47.8 ± 1.7, p < 0.001; Tp-e 82.3 ± 8.7/67.1 ± 5.1, p < 0.001; Tp-e/QTc 0.19 ± 0.01/0.17 ± 0.01, p < 0.001 (respectively)), statistically significant improvements were observed. A statistically significant dose-dependent decline in the magnitude of change in the QTc parameter (19.4/29.6, p = 0.038) was also observed. Conclusions: According to these results, empagliflozin may decrease the risk of potential ventricular arrhythmias.

14.
Antimicrob Agents Chemother ; 68(8): e0046424, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-38953364

RESUMEN

Islatravir is a deoxynucleoside analog being developed for the treatment of HIV-1 infection. Clinical studies are being conducted to evaluate islatravir, administered in combination with other antiretroviral therapies, at doses of 0.25 mg once daily and 2 mg once weekly. In multiple previous clinical studies, islatravir was generally well tolerated, with no clear trend in cardiac adverse events. A trial was conducted to evaluate the effect of islatravir on cardiac repolarization. A randomized, double-blind, active- and placebo-controlled phase 1 trial was conducted, in which a single dose of islatravir 0.75 mg, islatravir 240 mg (supratherapeutic dose), moxifloxacin 400 mg (active control), or placebo was administered. Continuous 12-lead electrocardiogram monitoring was performed before dosing through 24 hours after dosing. QT interval measurements were collected, and safety and pharmacokinetics were evaluated. Sixty-three participants were enrolled, and 59 completed the study. Fridericia's QT correction for heart rate was inadequate; therefore, a population-specific correction was applied (QTcP). The placebo-corrected change from baseline in QTcP (ΔΔQTcP) interval at the observed geometric mean maximum plasma concentration associated with islatravir 0.75 mg and islatravir 240 mg was <10 ms at all time points. Assay sensitivity was confirmed because the use of moxifloxacin 400 mg led to a ΔΔQTcP >10 ms. The pharmacokinetic profile of islatravir was consistent with that of previous studies, and islatravir was generally well tolerated. Results from the current trial suggest that single doses of islatravir as high as 240 mg do not lead to QTc interval prolongation.


Asunto(s)
Electrocardiografía , Fluoroquinolonas , Moxifloxacino , Humanos , Adulto , Masculino , Electrocardiografía/efectos de los fármacos , Método Doble Ciego , Femenino , Persona de Mediana Edad , Fluoroquinolonas/efectos adversos , Fluoroquinolonas/farmacocinética , Moxifloxacino/efectos adversos , Moxifloxacino/farmacocinética , Frecuencia Cardíaca/efectos de los fármacos , Síndrome de QT Prolongado/inducido químicamente , Adulto Joven , Fármacos Anti-VIH/farmacocinética , Fármacos Anti-VIH/efectos adversos , Fármacos Anti-VIH/uso terapéutico , Compuestos Aza/efectos adversos , Compuestos Aza/farmacocinética , Desoxiadenosinas
15.
J Toxicol Sci ; 49(6): 269-279, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38825486

RESUMEN

Although morphine has been used for treatment-resistant dyspnea in end-stage heart failure patients, information on its cardiovascular safety profile remains limited. Morphine was intravenously administered to halothane-anesthetized dogs (n=4) in doses of 0.1, 1 and 10 mg/kg/10 min with 20 min of observation period. The low and middle doses attained therapeutic (0.13 µg/mL) and supratherapeutic (0.97 µg/mL) plasma concentrations, respectively. The low dose hardly altered any of the cardiovascular variables except that the QT interval was prolonged for 10-15 min after its start of infusion. The middle dose reduced the preload and afterload to the left ventricle for 5-15 min, then decreased the left ventricular contractility and mean blood pressure for 10-30 min, and finally suppressed the heart rate for 15-30 min. Moreover, the middle dose gradually but progressively prolonged the atrioventricular conduction time, QT interval/QTcV, ventricular late repolarization period and ventricular effective refractory period without altering the intraventricular conduction time, ventricular early repolarization period or terminal repolarization period. A reverse-frequency-dependent delay of ventricular repolarization was confirmed. The high dose induced cardiohemodynamic collapse mainly due to vasodilation in the initial 2 animals by 1.9 and 3.3 min after its start of infusion, respectively, which needed circulatory support to treat. The high dose was not tested further in the remaining 2 animals. Thus, intravenously administered morphine exerts a rapidly appearing vasodilator action followed by slowly developing cardiosuppressive effects. Morphine can delay the ventricular repolarization possibly through IKr inhibition in vivo, but its potential to develop torsade de pointes will be small.


Asunto(s)
Anestésicos por Inhalación , Halotano , Frecuencia Cardíaca , Morfina , Animales , Perros , Morfina/administración & dosificación , Frecuencia Cardíaca/efectos de los fármacos , Anestésicos por Inhalación/administración & dosificación , Anestésicos por Inhalación/farmacocinética , Masculino , Toxicocinética , Relación Dosis-Respuesta a Droga , Analgésicos Opioides/administración & dosificación , Analgésicos Opioides/farmacocinética , Presión Sanguínea/efectos de los fármacos , Electrocardiografía/efectos de los fármacos , Femenino , Infusiones Intravenosas , Vasodilatación/efectos de los fármacos , Fenómenos Electrofisiológicos/efectos de los fármacos
16.
Kidney Int Rep ; 9(6): 1792-1801, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38899225

RESUMEN

Introduction: QT interval prolongation is a risk factor for fatal arrhythmias and other cardiovascular complications. QT interval prolongation in patients on hemodialysis (HD) is not well understood. Hypocalcemia is a suspected, but poorly verified etiology in these patients, and the association between serum phosphorus levels and QT interval prolongation is unknown. We sought to determine the prevalence of QT interval prolongation in patients on HD and to verify the association between predialysis serum calcium (Ca) and phosphate (P) levels and QT interval prolongation. Methods: A cross-sectional study was conducted on adult patients on maintenance HD who were enrolled in the Japanese Society for Dialysis Therapy and Renal Data Registry 2019. After assessing patient characteristics, linear regression analysis was performed with predialysis serum Ca and P levels as exposures and a rate-corrected QT (QTc) interval as the outcome. Results: A total of 204,530 patients were analyzed with a mean QTc of 451.2 (standard deviation, 36.9) ms. After multivariable analysis, estimated change in QTc (coefficients; 95% confidence interval) per 1 mg/dl increase in serum Ca and P was -2.02 (-3.00 to -1.04) and 5.50 (3.92-7.09), respectively. In the restricted cubic spline curve, estimated change in QTc increased with lower values of serum Ca. The correlation between serum P and QTc showed a U-shaped curve. Conclusion: Decreased serum Ca levels and decreased and increased serum P levels may be associated with QT interval prolongation in patients on maintenance HD.

17.
J Pharmacol Toxicol Methods ; 128: 107528, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38852684

RESUMEN

INTRODUCTION: In preclinical cardiovascular safety pharmacology studies, statistical analysis of the rate corrected QT interval (QTc) is the focus for predicting QTc interval changes in the clinic. Modeling of a concentration/QTc relationship, common clinically, is limited due to minimal pharmacokinetic (PK) data in nonclinical testing. It is possible, however, to relate the average drug plasma concentration from sparse PK samples over specific times to the mean corrected QTc. We hypothesize that averaging drug plasma concentration and the QTc-rate relationship over time provides a simple, accurate concentration-QTc relationship bridging statistical and concentration/QTc modeling. METHODS: Cardiovascular telemetry studies were conducted in non-human primates (NHP; n = 48) and canines (n = 8). Pharmacokinetic samples were collected on separate study days in both species. Average plasma concentrations for specific intervals (CAverage0-X) were calculated for moxifloxacin in canines and NHP using times corresponding to super-intervals for the QTc data statistical analysis. The QTc effect was calculated for each super-interval using a linear regression correction incorporating QT and HR data from the whole super-interval. The concentration QTc effects were then modeled. RESULTS: In NHP, a 10.9 ± 0.06 ms (mean ± 95% CI) change in QTc was detected at approximately 1.5× the moxifloxacin plasma concentration that causes a 10 ms QTc change in humans, based on a 0-24 h super-interval. When simulating a drug without QT effects, mock, no effect on QTc was detected at up to 3× the clinical concentration. Similarly, in canines, a 16.6 ± 0.1 ms change was detected at 1.7× critical clinical moxifloxacin concentration, and a 0.04 ± 0.1 ms change was seen for mock. CONCLUSIONS: While simultaneous PK and QTc data points are preferred, practical constraints and the need for QTc averaging did not prevent concentration-QTc analyses. Utilizing a 0-24 h super-interval method illustrates a simple and effective method to address cardiovascular questions when preclinical drug exposures exceed clinical concentrations.


Asunto(s)
Electrocardiografía , Síndrome de QT Prolongado , Moxifloxacino , Telemetría , Animales , Perros , Moxifloxacino/farmacocinética , Moxifloxacino/administración & dosificación , Electrocardiografía/efectos de los fármacos , Electrocardiografía/métodos , Telemetría/métodos , Síndrome de QT Prolongado/inducido químicamente , Evaluación Preclínica de Medicamentos/métodos , Fluoroquinolonas/farmacocinética , Fluoroquinolonas/administración & dosificación , Frecuencia Cardíaca/efectos de los fármacos , Masculino , Modelos Animales , Relación Dosis-Respuesta a Droga , Femenino
18.
J Clin Med ; 13(12)2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38930039

RESUMEN

Objectives: The association between anti-Ro/SSA antibodies and the appearance of cardiac rhythm disorders in adults is discussed. We aim to study this relationship, together with active treatments and comorbidities, and its impact on daily clinical practice in adults with systemic autoimmune diseases (SADs). Methods: This cross-sectional single-center study was conducted in a tertiary hospital between January 2021 and March 2022. A sample of adult patients followed up in the SAD Unit with a diagnosis of a SAD and previously tested for anti-Ro/SSA and anti-La/SSB were recruited. All of them underwent a 12-lead electrocardiogram. Results: 167 patients were included. 90 (53.9%) were positive for anti-Ro60, 101 (60.5%) for anti-Ro52, and 45 (26.9%) for anti-La/SSB; 52 (31.3%) were triple-negative. 84% were women, and the mean age was 59 years (standard deviation 12.8). The most common SAD was primary Sjögren's syndrome (34.8%), followed by systemic lupus erythematosus (24.6%) and rheumatoid arthritis (22.8%). A statistically significant relationship was found between anti-Ro52 positivity and cardiac rhythm disorders (relative risk = 2.007 [1.197-3.366]), specifically QTc prolongation (relative risk = 4.248 [1.553-11.615]). Multivariate regressions showed a significant association, with diabetes mellitus being the most related comorbidity. The association between anti-Ro52 antibodies and atrioventricular conduction disorders was not significant. Conclusions: The presence of anti-Ro52 antibodies in adult patients with SADs is associated with an increased risk of QTc prolongation. Electrocardiographic screening of patients with SAD, anti-Ro52 antibodies, and other risk factors, like diabetes mellitus or QT-prolonging drugs, seems advisable. Those with baseline electrocardiogram abnormalities or additional risk factors should undergo electrocardiographic monitoring.

19.
Cureus ; 16(5): e60492, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38882995

RESUMEN

Introduction Cancer chemotherapy regimens include multiple classes of adjuvant drugs as supportive therapy. Because of the concurrent intake of other drugs (like antiemetics, antidepressants, analgesics, and antimicrobials), there is a heightened risk for possible QT interval prolongation. There is a dearth of evidence in the literature regarding the usage of QT-prolonging anticancer drugs and associated risk factors that have the propensity to prolong QT interval. The purpose was to explore the extent of the use of QT-interval-prolonging drugs and potential QT-prolonging drug-drug interactions (QT-DDIs) in cancer patients attending OPD in a tertiary-care hospital. Methods This was a hospital-based, cross-sectional, observational study. Risk stratification of QT-prolonging drugs for torsades de pointes (TdP) was done by the Arizona Center for Education and Research on Therapeutics (AzCERT)/CredibleMeds-lists, and potential QT-DDIs were determined with four online DDI-checker-software. Results In 1331 cancer patients, the overall prevalence of potential QT-prolonging drug utilization was 97.3%. Ondansetron, pantoprazole, domperidone, and olanzapine were the most frequent QT-prolonging drugs in cancer patients. The top six antineoplastics with potential QT-prolonging and torsadogenic actions were capecitabine, oxaliplatin, imatinib, bortezomib, 5-fluorouracil, and bendamustine. Evidence-based pragmatic QTc interval prolongation risk assessment tools are imperative for cancer patients. Conclusion This study revealed a high prevalence of QT-prolonging drugs and QT-DDIs among cancer patients who are treated with anticancer and non-anticancer drugs. As a result, it's critical to take precautions, stay vigilant, and avoid QT-prolonging in clinical situations. Evidence-based pragmatic QTc interval prolongation risk assessment tools are needed for cancer patients.

20.
Arch Cardiovasc Dis ; 117(5): 313-320, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38704288

RESUMEN

BACKGROUND: In patients with congenital long QT syndrome (LQTS), the risk of ventricular arrhythmia is correlated with the duration of the corrected QT interval and the changes in the ST-T wave pattern on the 12-lead surface electrocardiogram (12L-ECG). Remote monitoring of these variables could be useful. AIM: To evaluate the abilities of two wearable electrocardiogram devices (Apple Watch and KardiaMobile 6L) to provide reliable electrocardiograms in terms of corrected QT interval and ST-T wave patterns in patients with LQTS. METHODS: In a prospective multicentre study (ClinicalTrials.gov identifier: NCT04728100), a 12L-ECG, a 6-lead KardiaMobile 6L electrocardiogram and two single-lead Apple Watch electrocardiograms were recorded in patients with LQTS. The corrected QT interval and ST-T wave patterns were evaluated manually. RESULTS: Overall, 98 patients with LQTS were included; 12.2% were children and 92.8% had a pathogenic variant in an LQTS gene. The main genotypes were LQTS type 1 (40.8%), LQTS type 2 (36.7%) and LQTS type 3 (7.1%); rarer genotypes were also represented. When comparing the ST-T wave patterns obtained with the 12L-ECG, the level of agreement was moderate with the Apple Watch (k=0.593) and substantial with the KardiaMobile 6L (k=0.651). Regarding the corrected QT interval, the correlation with 12L-ECG was strong for the Apple Watch (r=0.703 in lead II) and moderate for the KardiaMobile 6L (r=0.593). There was a slight overestimation of corrected QT interval with the Apple Watch and a subtle underestimation with the KardiaMobile 6L. CONCLUSIONS: In patients with LQTS, the corrected QT interval and ST-T wave patterns obtained with the Apple Watch and the KardiaMobile 6L correlated with the 12L-ECG. Although wearable electrocardiogram devices cannot replace the 12L-ECG for the follow-up of these patients, they could be interesting additional monitoring tools.


Asunto(s)
Frecuencia Cardíaca , Síndrome de QT Prolongado , Valor Predictivo de las Pruebas , Dispositivos Electrónicos Vestibles , Humanos , Síndrome de QT Prolongado/fisiopatología , Síndrome de QT Prolongado/diagnóstico , Síndrome de QT Prolongado/congénito , Síndrome de QT Prolongado/genética , Femenino , Masculino , Estudios Prospectivos , Niño , Adolescente , Adulto , Reproducibilidad de los Resultados , Adulto Joven , Electrocardiografía Ambulatoria/instrumentación , Potenciales de Acción , Preescolar , Diseño de Equipo , Factores de Tiempo , Persona de Mediana Edad , Electrocardiografía/instrumentación , Sistema de Conducción Cardíaco/fisiopatología
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