RESUMEN
BACKGROUND: Patients with heart failure undergoing cardiac resynchronization therapy with or without defibrillator function may exhibit recovery of left ventricular ejection fraction (LVEF) during follow-up. Mechanical dispersion (MD; the SD of time to peak longitudinal strain by two-dimensional speckle-tracking echocardiography) is a known predictor of life-threatening ventricular arrhythmias (VAs). Relationships among LVEF recovery, changes in MD, and incidence of VA are still not extensively investigated. METHODS: In this retrospective study, recipients of cardiac resynchronization therapy defibrillation (n = 183) or implantable cardioverter-defibrillators only (n = 87) underwent conventional and speckle-tracking echocardiography, both at baseline and after 10 to 12 months, and were followed clinically. Both a ≥10% increase in LVEF and a final LVEF > 35% defined echocardiographic response (EchoResp). Reduction in MD ≥10 msec defined MD response (MDResp). Risk for appropriate implantable cardioverter-defibrillator therapy for VAs was assessed using a multivariable Cox hazard model. RESULTS: The prevalence of EchoResp+ and MDResp+ was 39% and 46%, respectively. During follow-up (49.8 ± 33.5 months), 74 VA events occurred. The incidence rate (per 100 patient-years) of VAs was lowest in the EchoResp+/MDResp+ group (1.66%; 95% CI, 0.69%-3.99%), highest in the EchoResp-/MDResp- group (12.8%; 95% CI, 9.53%-17.2%; P < .0001), and intermediate in the EchoResp-/MDResp+ (5.5%; 95% CI, 3.3%-9.4%) or EchoResp+/MDResp- (5.3%; 95% CI, 3.0%-9.4%) group. Multivariable analysis showed that higher MD at follow-up (>71.4 msec) was associated with VAs independent of whether final LVEF was below or above the guideline-reported cutoff of 35% (P < .05). CONCLUSIONS: Among ICD recipients, improvements in both left ventricular function and MD are associated with reduced risk for VAs. In patients whose follow-up LVEFs improved to >35%, risk for VAs, although substantially decreased, remained elevated in the presence of still elevated MD.
Asunto(s)
Terapia de Resincronización Cardíaca , Desfibriladores Implantables , Ecocardiografía/métodos , Humanos , Estudios Retrospectivos , Factores de Riesgo , Volumen Sistólico , Función Ventricular IzquierdaRESUMEN
Exact natural history and physiopathology of takotsubo cardiomyopathy (TC) are incompletely understood. In the last years, a lot of special cases of TC appeared in the literature. This case report is a typical case of TC, which meets all Mayo Clinic diagnosis criteria, over the exceptions; its main feature is that it has both physical (medical) and emotional (psychiatric) triggers. The protagonist is a woman affected by anxious-depressive syndrome, hospitalized for a cardiogenic syncope. After pacemaker (PMK) implantation, she first has convulsive hysteric crisis, and the following day, she has a transient left ventricular apical ballooning without coronary artery stenosis: takotsubo syndrome. This case underlines the depth and strong relationship between takotsubo syndrome and psychiatric illness, which is both clinical substrate and triggering acute event, with the significant role of PMK implantation which might have had a role both as flare of psychiatric disease and as a trigger for the syndrome itself.