Asymptomatic primary mitral regurgitation due to myxomatous degeneration of the mitral valve leaflets may remain so for long periods, even as left ventricular function progresses to a decompensated stage. During the early compensated stage, the ventricle's initial response to the volume overload is an asymmetric increase in the diastolic short axis dimension, accomplished by a diastolic shift of the interventricular septum into the right ventricular cavity, creating a more spherical left ventricular diastolic shape, increasing diastolic filling and stroke volume. Early valve repair is recommended to reduce postoperative left ventricular dysfunction.
View Article and Find Full Text PDFParoxysmal interventricular septal motion (PSM) is the movement of the septum toward the right ventricle (RV) during cardiac systole. It occurs frequently after uncomplicated cardiac surgery (CS), including coronary bypass (on-pump and off-pump), valve repair or replacement, and with all types of incisions (sternotomy or mini-thoracotomy). It sometimes resolves quickly but may persist for months or become permanent.
View Article and Find Full Text PDFIdeal heart performance demands vigorous systolic contractions and rapid diastolic relaxation. These sequential events are precisely timed and interdependent and require the rapid synchronous electrical stimulation provided by the His-Purkinje system. Right ventricular (RV) pacing creates slow asynchronous electrical stimulation that disrupts the timing of the cardiac cycle and results in left ventricular (LV) mechanical asynchrony.
View Article and Find Full Text PDFBackground: Cardiac output is the fundamental determinant of peripheral blood flow however; optimal regional tissue perfusion is ultimately dependant on the integrity of the arterial conduits that transport flow. A complete understanding of tissue perfusion requires knowledge of both cardiac and peripheral blood flow. Existing noninvasive devices do not simultaneously assess the cardiac and peripheral circulations.
View Article and Find Full Text PDFObjectives: We sought to assess the ability of a new multi-channel electrical bioimpedance (MEB) methodology to accurately measure both cardiac blood flow and peripheral limb blood flow.
Background: Cardiac output is the primary determinant of peripheral blood flow; however, optimal regional tissue perfusion is ultimately dependent on the patency of the arterial conduits that transport that flow. A complete understanding of regional tissue perfusion requires knowledge of both cardiac and peripheral blood flow.
Congestive heart failure may be caused by late left ventricular (LV) dilation following anterior infarction. Early reperfusion prevents transmural necrosis, and makes the infarcted segment akinetic rather than dyskinetic. Surgical ventricular restoration (SVR) reduces LV volume and creates a more elliptical chamber by excluding scar in either akinetic or dyskinetic segments.
View Article and Find Full Text PDFAnterior myocardial infarction produces abrupt left ventricular (LV) dysynergy and global systolic dysfunction. Rapid intense neurohumoral activation, infarct expansion, and early ventricular chamber dilatation all contribute to restoring a normal stroke volume despite a persistently depressed ejection fraction. Continued neurohumoral activation provokes late remodeling of the remote non-infarcted myocardium, characterized by an abnormal progressively increasing LV volume/mass ratio that leads to further LV remodeling.
View Article and Find Full Text PDFObjectives: The purpose of this study was to test how surgical ventricular restoration (SVR) affects early and late survival in a registry of 1,198 post-anterior infarction congestive heart failure (CHF) patients treated by the international Reconstructive Endoventricular Surgery returning Torsion Original Radius Elliptical shape to the left ventricle (RESTORE)team.
Background: Congestive heart failure may be caused by late left ventricular (LV) dilation after anterior infarction. The infarcted segment is often akinetic rather than dyskinetic because early reperfusion prevents transmural necrosis.
This study examined the accuracy of a triglyceride/high-density lipoprotein (HDL) cholesterol ratio of 3.8 for the prediction of low-density lipoprotein (LDL) phenotype B. The ratio of 3.
View Article and Find Full Text PDFBackground: The purpose of this randomized, double-blind, placebo-controlled pilot study was to determine the effectiveness of an intravenous glucose-insulin-potassium (GIK) infusion in preventing myocardial damage and maintaining cardiac performance in patients undergoing "off-pump" myocardial revascularization.
Methods: Forty-six adult patients undergoing elective off-pump coronary artery bypass received either normal saline or a GIK infusion immediately after the induction of anesthesia through the first 12 hours of intensive care unit convalescence. Measurements of blood glucose, circulating creatine kinase MB and troponin I concentrations, as well as cardiac index (CI) and mixed venous oxygen saturation (SvO2), were obtained immediately before starting the infusion (baseline) and at 6, 12, and 24 hours post-initial coronary artery occlusion.