RESUMEN
AIMS: The maintenance of sinus rhythm is crucial for the functional capacity of patients with hypertrophic cardiomyopathy (HCM). Using a multimodality approach, we attempted to identify potential predictors of paroxysmal atrial fibrillation (PAF) in HCM patients. METHODS AND RESULTS: Thirty HCM patients (17 males, mean age 57.9 ± 13.6) with at least one documented PAF episode and 32 age- and sex-matched HCM control patients as well as 25 healthy volunteers were studied in sinus rhythm. Study subjects underwent 2D echocardiography including a colour Doppler myocardial imaging evaluation of the left atrium (LA). Additionally, an orthogonal electrocardiogram was acquired; P-wave duration, maximum, and mean energies were calculated for each subject at each orthogonal lead and the composite vector axis using the Morlet wavelet analysis. Compared with HCM controls, in HCM-PAF patients, LA antero-posterior diameter was significantly enlarged (LADAP: 46.1 ± 5.9 vs. 40.0 ± 4.7 mm, P < 0.001), peak strain rate of the LA lateral wall in the reservoir phase was significantly decreased (LAT peak SR-S: 1.93 ± 0.51 vs. 2.55 ± 0.83 s(-1), P < 0.01), and P-wave duration in the Z-lead was significantly prolonged (P-durZ: 106.9 ± 24.6 vs. 86.2 ± 14.3 ms, P < 0.001). Cut-off values and areas under the curve (AUCs) for individual parameters were 42.0 mm, 2.32 s(-1), and 98.8 ms and 0.81, 0.74, and 0.78, respectively. A multivariable model combining LADAP, LAT peak SR-S and P-durZ had an AUC of 0.90, a sensitivity of 0.87, and a specificity of 0.91 for identifying PAF patients. CONCLUSION: P-wave duration combined with LA antero-posterior diameter and myocardial deformation indices resulted in a higher power for discriminating HCM-PAF patients, when compared with individual parameters derived from either wavelet analysis or 2D echocardiography.
Asunto(s)
Fibrilación Atrial/diagnóstico , Cardiomiopatía Hipertrófica/diagnóstico , Ecocardiografía/métodos , Electrocardiografía/métodos , Taquicardia Paroxística/diagnóstico , Factores de Edad , Anciano , Análisis de Varianza , Fibrilación Atrial/complicaciones , Cardiomiopatía Hipertrófica/complicaciones , Estudios de Casos y Controles , Progresión de la Enfermedad , Femenino , Atrios Cardíacos/diagnóstico por imagen , Atrios Cardíacos/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Variaciones Dependientes del Observador , Pronóstico , Valores de Referencia , Estudios Retrospectivos , Medición de Riesgo , Sensibilidad y Especificidad , Factores Sexuales , Taquicardia Paroxística/complicaciones , Ultrasonografía Doppler en Color/métodosRESUMEN
BACKGROUND: Functional mitral valve regurgitation attenuation after cardiac resynchronization therapy (CRT) in patients with severe heart failure has been attributed to both the increased rate of left ventricular systolic pressure increase and to papillary muscle (PM) recoordinated contraction. We hypothesized that an increase in systolic deformation of the PMs or the adjacent myocardial wall may in part account for this effect, by preventing their outward displacement during systole. METHODS: We studied by echocardiography 22 patients with moderate/severe functional mitral valve regurgitation and a mean ejection fraction of 18 +/- 4% at baseline and after implantation of a CRT system. RESULTS: CRT induced a significant reduction of the effective regurgitant orifice area (0.18 +/- 0.11 vs 0.35 +/- 0.17 mm2, P < .001). Strain improved in both PMs and their adjacent walls, although this improvement was significant only in anterolateral PM (-16 +/- 4.7 vs -11 +/- 4.3%, P = .02) and posteromedial PM adjacent wall (-16 +/- 10 vs -8 +/- 4.6%, P = .01). CONCLUSIONS: CRT acutely reduces the severity of functional mitral valve regurgitation in patients with heart failure and this effect may be in part attributed to improved strain of PM or adjacent wall.