The effects of aetiology on outcome in patients treated with cardiac resynchronization therapy in the CARE-HF trial

Abstract

AimsCardiac dyssynchrony is common in patients with heart failure, whether or not they have ischaemic heart disease (IHD). The effect of the underlying cause of cardiac dysfunction on the response to cardiac resynchronization therapy (CRT) is unknown. This issue was addressed using data from the CARE-HF trial.Methods and resultsPatients (n = 813) were grouped by heart failure aetiology (IHD n = 339 vs. non-IHD n = 473), and the primary composite (all-cause mortality or unplanned hospitalization for a major cardiovascular event) and principal secondary (all-cause mortality) endpoints analysed. Heart failure severity and the degree of dyssynchrony were compared between the groups by analysing baseline clinical and echocardiographic variables. Patients with IHD were more likely to be in NYHA class IV (7.5 vs. 4.0%; P = 0.03) and to have higher NT-proBNP levels (2182 vs. 1725 pg/L), indicating more advanced heart failure. The degree of dyssynchrony was more pronounced in patients without IHD (assessed using mean QRS duration, interventricular mechanical delay, and aorta-pulmonary pre-ejection time). Left ventricular ejection fraction and left ventricular end-systolic volume improved to a lesser extent in the IHD group (4.53 vs. 8.50% and −35.68 vs. –58.52 cm3). Despite these differences, CRT improved all-cause mortality, NYHA class, and hospitalization rates to a similar extent in patients with or without IHD.ConclusionThe benefits of CRT in patients with or without IHD were similar in relative terms in the CARE-HF study but as patients with IHD had a worse prognosis, the benefit in absolute terms may be greater.

Early Cardiac Resynchronization Therapy and Reverse Remodeling in Patients With Mild Heart Failure

“…First, the magnitude of LV reverse remodeling in the cohort of nonischemic patients appears to be larger than in their ischemic counterparts. This is in contrast to the observations from CARE-HF, in which there were no discernible differences in degree of reverse remodeling after 3 months of CRT versus no CRT, 6 but is consistent with other prior studies with up to 12 months of follow-up. 7 Although the extent of viable or scarred myocardium can be postulated as a contributor, one should not forget that ventricular conduction delay itself can be the primary etiology of cardiac dysfunction, and hence an intervention that directly corrects such conduction abnormality may negate the root cause of cardiomyopathy.…”

Metabolic syndrome is associated with different clinical outcome after cardiac resynchronization therapy in patients with ischemic and non-ischemic cardiomyopathy

“…There was no evidence of differences in clinical benefit from CRT-D between ischemic and non-ischemic in non-obese patients. This is an unexpected finding, because non-ischemic cardiomyopathy patients were reported to present with better clinical re-sponse to CRT-D than ischemic cardiomyopathy ones [19][20][21]. Our current data indicate that these findings could be associated with the obesity and MS status.…”

2016 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure

“…Funkcja LV ulega mniejszej poprawie u pacjentów z bardziej rozległą blizną. Taka zależność jest jednak prawdziwa dla każdej metody leczenia HFrEF i obecność blizny nie jest wiarygodnym czynnikiem predykcyjnym gorszej odpowiedzi klinicznej [293]. Progi stymulacji są wyższe w obrębie blizny i, na ile to możliwe, elektrody komorowe powinny być położone w innej lokalizacji [294,295].…”