Effects of tribromoethanol anesthesia on echocardiographic assessment of left ventricular function in mice.

BACKGROUND AND PURPOSE: Pentobarbital and ketamine-xylazine anesthesia in mice result in markedly decreased left ventricular fractional shortening and cardiac output. However, to the authors' knowledge, the effect of short-acting, alcohol-based anesthesia on these parameters is unknown. METHODS: Fifteen mice (FVB/N, C57Bl/6J, A/J, n = 5 each) underwent high-resolution (15 MHz) 2-dimensional-directed M-mode echocardiography before and after undergoing 2.5% tribromoethanol anesthesia (0.01 ml/g of body weight). RESULTS: Tribromoethanol anesthesia resulted in significant heart rate slowing (29%) and left ventricular enlargement (20%), and a more modest (12%) reduction in left ventricular fractional shortening. Cardiac output was unchanged. The differences in left ventricular function between conscious and tribromoethanol studies were similar for each of the three strains of mice. CONCLUSIONS: Tribromoethanol anesthesia induced only modest effects on M-mode estimates of basal cardiac function and did not influence cardiac output. The effects to tribromoethanol anesthesia were similar among three commonly used mice strains.

Effect of angiotensin type I-receptor blockade on left ventricular remodeling in pressure overload hypertrophy.

BACKGROUND: The renin-angiotensin system is involved in cardiac remodeling. In contrast to the well-recognized salutary effects of angiotensin-converting enzyme inhibition, the value of angiotensin II type I (AT(1))-receptor blockade on left ventricular (LV) hypertrophy and dysfunction is controversial. METHODS AND RESULTS: Descending thoracic aorta-banded and sham-operated guinea pigs were given either losartan (30 mg x kg(-1) x day(-1) intraperitoneally) or vehicle for 8 weeks (n = 7 in each group). LV end-diastolic and end-systolic dimensions and wall thicknesses were measured echocardiographically, and LV fractional shortening, relative wall thickness, and LV mass normalized by body weight were calculated. Isolated heart function (Langendorff perfusion) was studied 8 weeks after surgery, and LV performance was assessed by maximum LV pressure and +/-dP/dt normalized by LV mass. Eight weeks after banding guinea pigs developed concentric LV hypertrophy and had decreased maximum LV pressure and +/-dP/dt normalized by LV mass; LV end-diastolic dimension and LV fractional shortening were unchanged. In band-operated guinea pigs treatment with losartan had no significant effects on any of these measurements. CONCLUSIONS: In guinea pigs with descending aortic banding, treatment with losartan for 8 weeks neither attenuates progression of pressure overload hypertrophy nor significantly improves impaired mass-normalized pressure-derived indices of LV contraction and relaxation.

Percutaneous balloon mitral valvulotomy with transesophageal echocardiographic monitoring: experience in Khon Kaen University.

To study the results and complications of Percutaneous Balloon Mitral Valvulotomy with Transesophageal Echocardiographic monitoring in patients with symptomatic mitral stenosis. From November 1996 to November 1998, PBMV with TEE monitoring was performed in 107 patients with symptomatic mitral stenosis. There were 72 females and 35 males, aged 19 to 65 years (mean 37.63). The mitral valve was successfully dilated in 104 patients. Immediately after PBMV, there was significant reduction of mean mitral valve gradient (17.89 +/- 6.7 mm Hg to 6.21 +/- 3.02 mm Hg), mean left atrial pressure (26.67 +/- 6.61 mm Hg to 13.97 +/- 4.7 mm Hg), mean pulmonary artery pressure (35.21 +/- 13.03 mm Hg to 27.71 +/- 10.31 mm Hg). Mitral valve area was increased from 0.80 +/- 0.24 cm2 to 1.75 +/- 0.42 cm2 and cardiac output was increased from 3.84 +/- 0.97 L/min to 4.74 +/- 1.09 L/min. Mitral regurgitation was detected in 20 patients, severe mitral regurgitaion appeared in one patient. None of these patients required emergency surgery. Cardiac tamponade was detected in one case and resolved by pericardiocentesis. TEE was well tolerated and no complications of TEE were detected. PBMV aided by TEE is safe and well tolerated.

Prevalence of cardiac arrhythmias in Thai community.

The resting 12 leads electrocardiogram was recorded in 3,822 men and 4,969 women (aged 30 years or over), who participated in the First National Health Examination Survey of Thailand and the data was used to determine the prevalence of cardiac arrhythmias. In this apparently normal population 362 subjects (the standard age adjusted rate was 39.2 per thousand) had cardiac arrhythmia. The prevalence rate of atrial fibrillation was 3.6 per thousand (males 3.6, females 3.6) and ventricular premature beat was 12.1 per thousand (males 7.3, females 15.6). For atrial premature beat, complete and incomplete right bundle branch blocks, sinus arrhythmia, first degree atrioventricular block and delta wave, the prevalence rates were 4.0, 7.0, 4.6, 2.7, 2.4 and 1.3 per thousand respectively. Complete and incomplete left branch blocks, left anterior hemiblock, second degree antrioventricular block and short PR interval were rare in this survey.

Left ventricular hypertrophy: relationship of echocardiographic and electrocardiographic findings in idiopathic dilated cardiomyopathy.

Diagnosis of left ventricular hypertrophy is important in patients with cardiac disease. To test the correlation of echocardiographic and electrocardiographic findings for diagnosis of left ventricular hypertrophy in Idiopathic Dilated Cardiomyopathy (IDC), 18 patients with proven IDC were examined. There were 15 males and 3 females, ages ranged from 22-60 years (mean 43 +/- 10.7). LV mass index ranged from 134.4-421.2 g/m2 (mean 187.8 +/- 68.6). All 18 patients had LVH by echocardiography but only 10 patients (55.6%) had LVH by using ECG Romhilt-Estes scoring system. The correlation between echocardiographic and electrocardiographic findings for diagnosis LVH was not significant (r = 0.026; p = 0.935) and echocardiography was better than electrocardiography for diagnosis of LVH in IDC.