Long-term Outcome Of Cardiac Resynchronization Therapy Research Articles

The role of acute invasive haemodynamic measurements in cardiac resynchronization therapy: looping towards prediction of long‐term response and therapy optimization

This editorial refers to ‘Prediction of long-term outcomeof cardiac resynchronization therapy by acute pressure–volume loop measurements’, by G.J. de Roest et al.doi.10.1093/eurjhf/hfs190Cardiac resynchronization therapy (CRT) has been established asan effective treatment strategy for heart failure patients withsevere LV systolic impairment and electrical dyssynchrony.

Fluoroscopic Left Ventricular Lead Position and the Long‐Term Clinical Outcome of Cardiac Resynchronization Therapy

To determine the effects of left ventricular (LV) lead tip position on the long-term outcome of cardiac resynchronization therapy (CRT). Cardiac device therapy center. Five hundred and fifty-six patients (age 70.4 ± 10.7 years [mean ± standard deviation]). CRT-pacing or CRT-defibrillation device implantation. Cardiovascular mortality and events over a maximum follow-up period of 9.1 years. Hazard ratios (HRs [95% 785]797) for cardiovascular mortality, adjusted for age, gender, QRS duration, heart failure etiology, New York Heart Association class, and presence of diabetes and atrial fibrillation, were derived for LV lead tip positions in terms of veins, circumferential, and longitudinal positions with respect to the LV chamber. For vein position, these were 1.07 (0.74-1.56) for anterolateral vein position and 1.24 (0.79-1.95) for the middle cardiac vein, compared with a posterolateral vein. For circumferential lead tip position, HRs were 1.56 (0.73-3.34) for anterolateral and 1.57 (0.76-3.25) for lateral, compared with posterior positions. For longitudinal lead tip positions, HRs were 1.02 (0.72-1.46) for basal and 1.21 (0.68-2.17) for apical, compared with mid-ventricular positions. The risk of meeting the composite endpoints of cardiovascular death or hospitalizations for heart failure and death from any cause or hospitalizations for major adverse cardiovascular events was similar among the various LV lead tip positions. The position of the LV lead over the LV free wall, assessed by fluoroscopy, has no influence over the long-term outcome of CRT.

Differential outcome of cardiac resynchronization therapy in ischemic cardiomyopathy and idiopathic dilated cardiomyopathy

Cardiac resynchronization therapy (CRT) is a therapy of proven benefit in patients with advanced heart failure. Identifying potential responders remains challenging, and whether the etiology of the heart failure is related to the potential hemodynamic benefit and long-term outcome of CRT is unclear. The purpose of this study was to evaluate whether heart failure etiology (ischemic cardiomyopathy [ICM] vs nonischemic dilated cardiomyopathy [DCM]) was associated with CRT outcome and implantable cardioverter-defibrillator (ICD) shocks. The study included 503 CRT recipients (CRT-D 90%) in a longitudinal CRT database: ICM (n = 312) and DCM (n = 191). Clinical variables and echocardiographic measures preimplant and postimplant were collected. Actuarial survival and ICD therapy data were assessed with Kaplan-Meier curve and log rank tests. Pre-CRT, ICM patients were older and had higher creatinine levels (P <.001). At median follow-up of 7.1 months, the DCM group experienced greater improvement in left ventricular ejection fraction (8.3% ± 10% vs 6.2% ± 10%, P = .05) and left ventricular end-diastolic volumes than did those with ICM (-28%.4 ± 53 mL vs -15.3 ± 46 mL, P = .024). Survival estimates at 4 years were 55% for ICM and 77% for DCM groups (P <.001), respectively, whereas no significant difference in the incidence of appropriate/inappropriate ICD shocks was observed. The ICM group remained at higher risk for death compared to the DCM group after controlling for preimplant variables (hazard ratio 1.6, 95% confidence interval 1.1-2.3, P = .008). In response to CRT and in contrast to ICM, DCM patients experienced greater improvement in left ventricular systolic function and reverse remodeling while also sustaining a greater survival benefit.

Long‐Term Follow‐Up of Patients with Refractory Heart Failure and Myocardial Ischemia Treated with Cardiac Resynchronization Therapy

Studies in patients without coronary artery disease have shown the restoration of glucose metabolism by cardiac resynchronization therapy (CRT) without changes in myocardial perfusion. We report on the long-term outcome of CRT in 24 patients with severe heart failure (HF) and advanced coronary artery disease not amenable for revascularization. All patients had documented myocardial ischemia on stress (99)Tc-sestamibi single-photon emission computed tomography, and all underwent successful implantations of CRT systems. The mean left ventricular ejection fraction was 21%+/- 4%, 19 patients (79%) had anginal complaints and 20 (83%) had diffuse three-vessel disease. During a follow-up of 13 +/- 0.7 months, two patients died suddenly and one died of progressive HF. Among survivors, functional capacity decreased from New York Heart Association class 3.2 +/- 1.4 to 2.1 +/- 1.0 (P < 0.01), and the Minnesota questionnaire quality-of-life scores decreased from 43 +/- 15 to 28 +/- 13 (P < 0.01). Despite an increase from 264 +/- 104 to 385 +/- 121 m in distance walked in 6 minutes (P < 0.01), the number of anginal attacks/week remained unchanged (4.7 +/- 0.7 to 4.5 +/- 0.6). Patients with advanced HF, stable angina, and documented myocardial ischemia may undergo safe and successful implantations of CRT systems.