Effects of hypobaric hypoxia exposure at high altitude on left ventricular twist in healthy subjects: data from HIGHCARE study on Mount Everest.

Aims: Previous studies investigating the effect of hypoxia on left ventricle focused on its global function, an approach that may not detect a selective dysfunction of subendocardial layers that are most sensitive to an inadequate oxygen supply. In the HIGHCARE study, aimed at exploring the effects of high altitude hypoxia on multiple biological variables and their modulation by an angiotensin receptor blocker, we addressed the effects of hypobaric hypoxia on both systolic and diastolic left ventricular geometry and function, focusing on echocardiographic assessment of left ventricle twist to indirectly examine subendocardial left ventricular systolic function.

Methods And Results: In 39 healthy subjects, physiological and echocardiographic variables, including left ventricular twist and a simplified torsion-to-shortening ratio (sTSR), were recorded at sea level, at 3400 m, and at 5400 m altitude (Mount Everest base camp).

Left-to-right systolic ventricular interaction in patients undergoing biventricular stimulation for dilated cardiomyopathy.

Left-to-right systolic ventricular interaction (i.e., the phenomenon by which the left ventricle contributes to most of the flow and to two-thirds of the pressure generated by the right ventricle) originates from transmission of systolic forces between the ventricles through the interventricular septum and from the mechanical effect of the common muscle fibers encircling their free walls.

Improvement in left ventricular diastolic stiffness induced by physical training in patients with dilated cardiomyopathy.

Background: Diastolic dysfunction in long-term heart failure is accompanied by abnormal neurohormonal control and ventricular stiffness. The diastolic phase is determined by a balance between pressure gradients and intrinsic ventricular wall properties: according to a mathematical model, the latter (ie, left ventricular [LV] elastance, K(LV)) may be calculated by the formula: K(LV) = (70/[DT-20])(2) mm Hg/mL, where DT is the transmitral Doppler deceleration time.

Methods And Results: In 54 patients with chronic systolic heart failure (39 men, 15 women; age 65 +/- 10 years; New York Heart Association [NYHA], 2.

Percutaneous bridge to heart transplantation by venoarterial ECMO and transaortic left ventricular venting.

We report a case in which life support for cardiogenic shock was achieved by a nonpulsatile venoarterial bypass, and left ventricular decompression was obtained by a catheter placed percutaneously through the aortic valve into the left ventricle. The blood drained from the left ventricle was pumped into the femoral artery. The normalization of left heart filling pressures allowed the resolution of pulmonary edema, and the patient underwent a successful heart transplantation following 7 days of mechanical cardiocirculatory support.