CorVue algorithm efficacy to predict heart failure in real life: Unnecessary and potentially misleading information?

BACKGROUND: Heart failure (HF) hospitalizations have a negative impact on quality of life and imply important costs. Intrathoracic impedance (ITI) variations detected by cardiac devices have been hypothesized to predict HF hospitalizations. Although Optivol™ algorithm (Medtronic, Minneapolis, MN, USA) has been widely studied, CorVue™ algorithm's (St. Jude Medical, St. Paul, MN, USA) long-term efficacy has not been systematically evaluated in a "real-life" cohort. METHODS: CorVue™ was activated in implantable cardioverter defibrillator (ICD)/cardiac resynchronization therapy defibrillator (CRT-D) patients to store information about ITI measures. Clinical events (new episodes of HF requiring treatment and hospitalizations) and CorVue™ data were recorded every 3 months. Appropriate CorVue™ detection for HF was considered if it occurred in the 4 prior weeks to the clinical event. RESULTS: Fifty-three ICD/CRT-D (26 ICD and 27 CRT-D) patients (67 ± 1 years old, 79% male) were included. Device position was subcutaneous in 28 patients. At inclusion, mean left ventricular ejection fraction was 25 ± 7% and 27 patients (51%) were in New York Heart Association class I, 18 (34%) in class II, and eight (15%) in class III. After a mean follow-up of 17 ± 9 months, 105 ITI drops alarms were detected in 32 patients (60%). Only six alarms were appropriate (true positive) and required hospitalization. Eighteen patients (34%) presented 25 clinical episodes (12 hospitalizations and 13 emergency room/ambulatory treatment modifications). Nineteen of these clinical episodes (76%) remained undetected by the CorVue™ (false negative). Sensitivity of CorVue™ resulted in 24%, specificity was 70%, positive predictive value of 6%, and negative predictive value of 93%. CONCLUSIONS: CorVue™ showed a low sensitivity to predict HF events. Therefore, routinely activation of this algorithm could generate misleading information.

Beta-blocker therapy in elderly patients with renal dysfunction and heart failure.

OBJECTIVE: To assess the role of beta-blockers (BB) in patients with chronic kidney disease (CKD) aged ≥ 75 years. METHODS AND RESULTS: From January 2008 to July 2014, we included 390 consecutive patients ≥ 75 years of age with ejection fraction ≤ 35% and glomerular filtration rate (GFR) ≤ 60 mL/min per 1.73 m2. We analyzed the relationship between treatment with BB and mortality or cardiovascular events. The mean age of our population was 82.6 ± 4.1 years. Mean ejection fraction was 27.9% ± 6.5%. GFR was 60-45 mL/min per 1.73 m2 in 50.3% of patients, 45-30 mL/min per 1.73 m2 in 37.4%, and < 30 mL/min per 1.73 m 2 in 12.3%. At the conclusion of follow-up, 67.4% of patients were receiving BB. The median follow-up was 28.04 (IR: 19.41-36.67) months. During the study period, 211 patients (54.1%) died and 257 (65.9%) had a major cardiovascular event (death or hospitalization for heart failure). BB use was significantly associated with a reduced risk of death (HR = 0.51, 95% CI: 0.35-0.74;P < 0.001). Patients receiving BB consistently showed a reduced risk of death across the different stages of CKD: stage IIIa (GFR = 30-45 mL/min per 1.73 m 2; HR = 0.47, 95% CI: 0.26-0.86,P < 0.0001), stage IIIb (GFR 30-45 mL/min per 1.73 m 2; HR = 0.55, 95% CI: 0.26-1.06,P = 0.007), and stages IV and V (GFR < 30 mL/min per 1.73 m 2; HR = 0.29, 95% CI: 0.11-0.76;P = 0.047). CONCLUSIONS: The use of BB in elderly patients with HFrEF and renal impairment was associated with a better prognosis. Use of BB should be encouraged when possible.

Comparison of pharmacological treatment alone vs. treatment combined with implantable cardioverter defibrillator therapy in patients older than 75 years.

AIMS: Implantable cardioverter defibrillator (ICD) reduces mortality in selected patients. However, its role in patients older than 75 years is not well established. METHODS AND RESULTS: We performed a retrospective, non-randomized study using a historical cohort from a single centre. Between January 2008 and July 2014, we assessed patients aged ≥75 years with left ventricular ejection fraction ≤ 35%, identifying 385 patients with a Class I or IIa recommendation for ICD implantation. At the decision of the patient or attending cardiologists, 92 patients received an ICD. To avoid potential confounding factors, we used propensity-score matching. Finally, 126 patients were included (63 with ICD). The mean age was 79.1 ± 3.1 years (86.5% male). As compared with the medical therapy group, the ICD patients had a lower percentage of chronic obstructive pulmonary disease (19.0% vs. 38.1%, P < 0.05) and more frequent use of beta-blockers (BBs) (85.7 vs. 70.0%, P < 0.05). Other treatments were otherwise similar in both groups. There were no differences related to age, aetiology, or other co-morbidities. During follow-up (39.2 ± 22.4 months), total mortality was 46.0% and cardiovascular events (death or hospitalization) occurred in 66.7% of the patients. A multivariate analysis revealed that only BB therapy was shown to be an independent protective variable with respect to mortality [hazard ratio 0.4 (0.2-0.7)]. ICD therapy did not reduce overall mortality or the rate of cardiovascular events. CONCLUSIONS: According to our results, the use of ICD, as compared with medical therapy, in patients older than 75 years did not demonstrate any benefit. Well-designed randomized controlled studies in patients older than 75 years are needed to ascertain the value of ICD therapy.

Usefulness of speckle myocardial imaging modalities for differential diagnosis of left ventricular non-compaction of the myocardium.

BACKGROUND/OBJECTIVES: Current diagnostic criteria for left ventricular non-compaction (LVNC) may result in over-diagnosis of the disease. We evaluate the role of speckle imaging in differential diagnosis of LVNC. METHODS AND RESULTS: We included all patients who, between January 2012 and May 2015, fulfilled currently accepted criteria for LVNC (28 patients). A control group of 28 healthy individuals and a third group of 13 patients with dilated cardiomyopathy (DCM) were created. Speckle-tracking echocardiography was performed in all groups. Thirteen patients with LVNC had an ejection fraction (EF) <50% (33.5%, SD 10). When compared to controls, patients with LVNC and EF<50% had a larger LV, larger left atrial diameter (LA), reduced e', and reduced global longitudinal strain (GLS). All but one patient with LVNC and EF<50% showed an abnormal LV rotation. This abnormal pattern was observed in 4 LVNC patients (27%) with EF≥50% and in none of the controls. In patients with LVNC, EF ≥50%, and abnormal rotation, GLS was lower than in controls, (-17 (SD 3) vs -21 (SD 3)). Rigid body rotation (RBR) was also observed in 2 DCM patients, with significant differences in EF, GLS, LV diameters relative to the rest of the DCM group. CONCLUSIONS: In patients who fulfil the morphologic criteria for LVNC, speckle myocardial imaging techniques could be useful in differentiating between healthy individuals (functionally normal LV) and patients with LVNC (with functional abnormalities in the myocardium in spite of a preserved EF).

Relationship between different doses of beta-blockers and prognosis in elderly patients with reduced ejection fraction.

BACKGROUND: Beta-blockers (BBs) remain underused in elderly patients with reduced ejection fraction (REF). Our aim was to determine the prognostic impact of different doses of BB in this setting. METHODS AND RESULTS: A single-center observational study was conducted. Inclusion criteria were age≥75 and EF≤0.35. Six months after diagnosis, patients were divided into 3 groups depending on BB dose: no BB (NBB), low dose (<50% of the target dose) (LD), and high dose (≥50%) (HD). Two different analytical approaches were employed: multivariate Cox model and propensity-score (PS) matching. Outcomes were all-cause death and heart failure (HF) admission. We included 559 patients (134 NBB, 259 LD, and 166 HD) with median follow-up of 29.9months. There were 212 deaths (NBB: 70 (52.2%); LD: 94 (36.3%); and HD: 48 (28.9%)) and 171 HF admissions (NBB: 42 (31.3%); LD: 85 (32.8%); and HD: 44 (26.5%)). On multivariate analysis, both LD and HD were associated with improved survival, with no differences between them (HD vs. NBB=0.67, 95% CI=[0.46-0.98], p=0.037; HD vs. LD=1.03, 95% CI=[0.72-1.46], p=0.894; and LD vs. NBB=0.65, 95% CI=[0.48-0.90], p=0.009). However, BB therapy failed to show benefits in HF admissions (p=NS, for each comparison). PS-matched analysis included 198 patients, with similar results to those mentioned above. CONCLUSIONS: BB therapy was associated with a significant reduction in mortality among elderly patients with REF, regardless of dose. Nevertheless, it was not associated with a decrease in HF admissions. Further studies are needed to determine the optimal BB dose in these patients.

Comparison of pharmacological treatment alone versus treatment combined with cardiac resynchronization therapy in patients over 75 years.

BACKGROUND: The role of cardiac resynchronization therapy (CRT) in patients aged ≥75 years is not well established. METHODS: We identified 607 patients aged ≥75 years with left ventricular ejection fraction (LVEF) of ≤35 %, of whom 78 met the guidelines for indication of CRT. Based on the decision of the patients or attending cardiologists, 34 patients received a CRT defibrillator (CRT-D). RESULTS: The age of patients with a CRT indication was 80 ± 4 years, and 73 % were males. As compared with patients on medical therapy, CRT-D patients were younger (79 ± 3 vs. 83 ± 4, P < 0.001), had lower LVEF (23 ± 7 vs. 27 ± 7 %, P = 0.008) and higher rate of decompensated heart failure episodes (77 vs. 55 %, P = 0.04), were more frequently New York Heart Association (NYHA) class III-IV (53 vs. 25 %, P = 0.01), and were more likely to be on beta-blockers (88 vs. 66 %, P = 0.023), anticoagulants (61 vs. 32 % P = 0.02), and anti-aldosterone drugs (82 vs. 50 %, P = 0.003). After a median follow-up of 26 months, seven patients in the CRT-D group (21 %) and 20 non-CRT patients (46 %) died (hazard ratio (HR) 0.16 [95 % confidence interval (CI) 0.06-0.46]). The end point of mortality or hospitalization was not reduced because of a similar rate of hospitalizations for heart failure of CRT-D patients. Four CRT-D patients (12 %) had received appropriate device therapy, and one had been inappropriately discharged. During follow-up, 44 % of CRT-D patients improved their LVEF by >40 %. CONCLUSION: CRT-D is potentially of benefit in terms of mortality in our population; this effect persists after correction for use of beta-blockers. In patients ≥75 years, CRT indications should be similar to those accepted for younger subjects.

Pure right ventricular infarction resulting from coronary ectasia: importance of diagnostic imaging.

Isolated right ventricular (RV) infarction may occur during percutaneous coronary intervention resulting from selective occlusion of a ventricular branch of the right coronary artery (RCA). We present a case of a pure RV infarction without iatrogenic origin that at the initial electrocardiographic analysis was suggestive of a left anterior descending artery-related acute myocardial infarction. Coronary angiography results made us suspect thrombotic occlusion of a small branch of the ectatic RCA resulting from slow flow. Final diagnosis was confirmed by coronary computed tomographic angiography and cardiac magnetic resonance imaging, underlining the essential diagnostic role of these imaging modalities.