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The article focuses on a study that assessed the safety and feasibility of permanent implantation of a novel coronary sinus mitral repair device or percutaneous transvenous mitral annuloplasty (PTMA). The study used patients with primarily functional mitral regurgitation (MR). Sustained reductions of mitral annulus septal-lateral dimension were observed in patients with the implants. It concluded that the percutaneous implantation of the device is feasible and safe.

Background: Electrocardiography (ECG) requires the application of electrodes to the skin and often necessitates undressing. Capacitively coupled electrodes embedded in a normal chair would be a rational alternative for ECG screening. We evaluated the reliability and accuracy of ECG electrodes imbedded in a chair cushion., Methods: Two independent clinicians compared ECG recordings obtained using skin electrodes with recordings obtained using capacitively coupled electrodes that were embedded in a chair cushion in an anesthesiology premedication room, a cardiology outpatient ward, and a cardiology day ward. We analyzed the data to compare the sensitivity and specificity for the diagnosis of cardiac arrhythmias., Results: ECG recordings were obtained from 107 patients. Heart rate was accurately measured using the capacitively coupled electrodes, but motion artifacts made the identification of P and T waves unreliable. Signal quality was poor for patients with low body weight, patients wearing clothing containing mixed fibers, and patients wearing sweaty shirts., Conclusions: Heart rate was accurately measured, and some cardiac arrhythmias were correctly diagnosed using capacitive ECG electrodes. Capacitive electrodes embedded into an examination chair are a promising tool for preoperative screening. Improved artifact reduction algorithms are needed before capacitive electrodes will replace skin electrodes.

Background: Electric stimulation of mediastinal sympathetic cardiac nerves increases cardiac contractility but is not selective for the left ventricle because it elicits sinus tachycardia and enhanced atrioventricular conduction. The aim of this study was to identify sympathetic neural structures inside the heart that selectively control left ventricular inotropy and can be accessed by transvenous catheter stimulation., Methods and Results: In 20 sheep, high-frequency stimulation (200 Hz) during the myocardial refractory period with electrode catheters inside the coronary sinus evoked a systolic left ventricular pressure increase from 97+/-20 to 138+/-32 mm Hg (P<0.001) without changes in sinus rate or PR time. Likewise, the rate of systolic pressure development (1143+/-334 versus 1725+/-632 mm Hg/s; P=0.004) and rate of diastolic relaxation (531+/-128 versus 888+/-331 mm Hg/s; P=0.001) increased. The slope of the end-systolic pressure-volume relationship increased (2.3+/-0.8 versus 3.1+/-0.6 mm Hg/mL; P=0.04), as did cardiac output (3.5+/-0.8 versus 4.4+/-0.8 L/min; P<0.001). Systemic vascular resistance and right ventricular pressure remained unchanged. There was a sigmoid dose-response curve. Ultrasound analysis revealed an increase in circumferential and radial strain in all left ventricular segments that was significant for the posterior, lateral, and anterior segments. Pressure effects were maintained for at least 4 hours of continued high-frequency stimulation and abolished by beta1-receptor blockade. Histology showed distinct adrenergic nerve bundles at the high-frequency stimulation site., Conclusions: Cardiac nerve fibers that innervate the left ventricle are amenable to transvenous electric catheter stimulation. This may permit direct interference with and modulation of the sympathetic tone of the left ventricle.