non-invasive ultrasound surgeries such as high intensity focused ultrasound have been developed to treat tumors or to stop bleeding. in this technique, incorporation of a suitable imaging modality to monitor and control the treatments is essential so several imaging methods such as x-ray, magnetic resonance imaging and ultrasound imaging have been proposed to monitor the induced thermal lesions...

Mechanical alternans is observed in patients with severe left ventricular dysfunction. We report a case of dilated cardiomyopathy with mechanical alternans. He presented with a remarkable decrease in plasma brain natriuretic peptide (BNP) levels after beta-blocker therapy despite persistency of the mechanical alternans. Mechanical alternans may persist after improvement of hemodynamics, diastol...

In concept, mechanical interventions are attractive options for treating acute myocardial infarction with or without preceding thrombolysis: rapid reperfusion of the infarct-related artery can be achieved in the vast majority of cases, and the underlying coronary lesion is treated at the same time. Various strategies have been extensively investigated. When performed in specialized centres, dir...

The effects of an extracellular sodium (Na) concentration of 200 mM on function, ionic exchange, and water movements were examined in the vascularly perfused rabbit intraventricular septum. When the perfusate was switched from 142 mMNa to 200 mMNa, dP/ dt fell 20.4% over 2 minutes; dP/dt then recovered to the control level. The time course of the functional recovery correlated with the uptake o...

Rupture of the left ventricular myocardium during the course of an acute myocardial infarction may affect the free wall, the interventricular septum, or the papillary muscles. When a rupture occurs, it is referred to as a mechanical complication of acute myocardial infarction. All mechanical complications may lead to cardiogenic shock. However, the location of the rupture can often be suspected...

OBJECTIVE To outline the outcome and management of patients with acute myocardial infarction presenting with mechanical complications such as post-infarction ventricular septal defect, mitral regurgitation and left ventricular rupture. METHODS The retrospective study, conducted in September and October, 2010 at the Aga Khan University Hospital, Karachi, included cases from January 1990 to Dec...

BACKGROUND Extracellular matrix (ECM), a tissue-engineered scaffold, recently demonstrated cardiomyocyte population after myocardial implantation. Surgical restoration of myocardium frequently uses Dacron as a myocardial patch. We hypothesized that an ECM-derived myocardial patch would provide a mechanical benefit not seen with Dacron. METHODS AND RESULTS Using a canine model, a full thicknes...

OBJECTIVES We sought to evaluate the effects of mechanical thrombectomy on myocardial reperfusion during direct angioplasty for acute myocardial infarction (AMI). BACKGROUND Embolization of thrombus and plaque debris may occur during direct angioplasty for AMI. This may lead to distal vessel or side branch occlusion and to obstructions in the microvascular system, resulting in impaired myocar...

Myocardial electrical impedance is influenced by the mechanical activity of the heart. Therefore, the ischemia-induced mechanical dysfunction may cause specific changes in the systolic-diastolic pattern of myocardial impedance, but this is not known. This study aimed to analyze the phasic changes of myocardial resistivity in normal and ischemic conditions. Myocardial resistivity was measured co...