Synchronized diaphragmatic stimulation for heart failure using the VisONE system: a first-in-patient study.

AIMS: Synchronized diaphragmatic stimulation (SDS) modulates intrathoracic and intra-abdominal pressures with favourable effects on cardiac function for patients with a reduced left ventricular ejection fraction (LVEF) and heart failure (HFrEF). VisONE-HF is a first-in-patient, observational study assessing the feasibility and 1 year effects of a novel, minimally invasive SDS device. METHODS AND RESULTS: The SDS system comprises a pulse generator and two laparoscopically delivered, bipolar, active-fixation leads on the inferior diaphragmatic surface. Fifteen symptomatic men with HFrEF and ischaemic heart disease receiving guideline-recommended therapy were enrolled (age 60 [56, 67] years, New York Heart Association class II [53%] /III [47%], LVEF 27 [23, 33] %, QRSd 117 [100, 125] ms, & N terminal pro brain natriuretic peptide [NT-proBNP] 1779 [911, 2,072] pg/mL). Implant success was 100%. Patients were evaluated at 3, 6, and 12 months for device-related or lead-related complications, quality of life (SF-36 QOL), 6 min hall walk distance (6MHWd), and by echocardiography. No implant procedure or SDS-related adverse event occurred, and patients were unaware of diaphragmatic stimulation. By 12 months, left ventricular end-systolic volume decreased (136 [123, 170] mL to 98 [89, 106] mL; P = 0.05), 6MHWd increased (315 [300, 330] m to 340 [315, 368] m; P = 0.004), and SF-36 QOL improved (physical scale 0 [0, 0] to 25 [0, 50], P = 0.006; emotional scale 0 [0, 33] to 33 [33, 67], P = 0.001). Although neither reached statistical significance, LVEF decreased (28 [23, 40]% vs. 34 [29, 38]%; P = ns) and NT-proBNP was lower (1784 [920, 2540] pg/mL vs. 1492 [879, 2028] pg/mL; P = ns). CONCLUSIONS: These data demonstrate the feasibility of laparoscopic implantation and delivery of SDS without raising safety concerns. These encouraging findings should be investigated further in adequately powered randomized trials.

Is surgery the gold standard in the treatment of obstructive hypertrophic cardiomyopathy?

OBJECTIVES: Hypertrophic cardiomyopathy is a complex and relatively common genetic cardiac disease and has been the subject of intensive scrutiny and investigation for over 40 years. The aim of this non-randomized cohort study was to compare subjective and objective outcomes in hypertrophic cardiomyopathy patients undergoing drug therapy, surgical myotomy-myectomy, dual-chamber pacing and alcohol septal ablation. METHODS: We examined 194 patients: 103 with non-obstructive hypertrophic cardiomyopathy and 91 with obstructive hypertrophic cardiomyopathy. All the patients with a non-obstructive form were on drug therapy. Ninety-one consecutive patients with drug-refractory obstructive hypertrophic cardiomyopathy were treated invasively. Dual-chamber pacemaker implantation was performed for 49 patients with previous positive temporary pacing test (Group 1). In 28 patients with massive left ventricle hypertrophy and obliteration of its cavities, extensive myotomy-myectomy was performed (Group 2). In 14 patients with midventricular obstruction and appropriate coronary anatomy, alcohol septal ablation was performed (Group 3). RESULTS: The peak left ventricle outflow tract gradient was 84.1 ± 15.2 mmHg in Group 1, 113.3 ± 14.9 mmHg in Group 2 and 97.5 ± 8.9 mmHg in Group 3. Dual-chamber pacing in Group 1 with optimal atrio-ventricular delay (85-180 ms for atrium pacing and 45-120 ms for atrial sensing) leads to dramatic decreases in left ventricle outflow tract gradient to 17.6 ± 11.8 mmHg and degree of mitral regurgitation. After extensive myectomy in Group 2, we observed a reduction of left ventricle outflow tract gradient to 17.3 ± 10.2 mmHg. Septal alcohol ablation in Group 3 leads to a left ventricle outflow tract gradient decrease from 97.5 ± 8.9 to 25.3 ± 5.8 mmHg. CONCLUSIONS: Surgical myectomy, dual-chamber pacing and alcohol septal ablation are equally effective in reducing obstruction in case of correct indications. Dual-chamber pacing is indicated in functional reversible states characterized by excitation delay. Alcohol septal ablation is preferable in cases with midventricular obstruction and appropriate coronary anatomy. Surgical methods are indicated in anatomical irreversible changes and remain the gold standard for obstructive hypertrophic cardiomyopathy treatment.