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The effects of heart failure on the expression of the sarcoplasmic reticulum (SR) calcium-adenosine triphosphatase (Ca2+-ATPase) and the subsequent effect on contractility was investigated in isolated myocyte from dogs with pacing-induced heart failure and normal controls. Results reveal that heart failure depresses the expression of Ca2+-ATPase resulting in a reduction in SR calcium uptake. This leads to a depression in myocardial contractility.

The left ventricular (LV) heart muscles of rats with pressure overload and sham-operated rats were analyzed to determine the effects of pressure overload on Ca2+-regulatory proteins in the sarcoplasmic reticulum (SR). Aortic-constricted rats exhibited impaired LV myocyte contractile function and reduced levels of SR Ca2+-regulatory proteins. Furthermore, SR Ca2+-adenosine triphosphatase activity was altered by cardiac hypertrophy.

Previous studies have shown that myocyte contractile dysfunction results from an increase in microtubules that form the intracellular network of cardiac myocytes. Herein, experiments using rats subjected to pressure-overload left ventricle hypertrophy revealed that myocyte contractile dysfunction during heart failure is caused by persistent pressure overloading to the myocardium as a result of the increases in microtubules.

Determines the functional consequence of a decreased expression of sarcoplasmic reticulum (SR) Ca[sup 2+]-ATPase in tachycardia-induced heart failure. Myocyte contractile function and gene expression of SR Ca[sup 2+]-ATPase; Effects of thapsigargin and cyclopiazonic acid on contractile function and intracellular free Ca[sup 2+] concentration transient in normal myocytes.

A survey by the Japanese Coronary Intervention Study (JCIS) group revealed that 109,788 percutaneous coronary intervention (PCI) procedures were performed at 1,023 laboratories during 1997. The present study aimed to describe the demographic and clinical characteristics, treatment strategies, in-hospital outcomes, and long-term outcomes of these patients. A total of 10,642 PCIs performed in 8,814 patients, which corresponded to approximately 10% of the overall PCIs, were selected at random. The mean patient age was 65 years, and 75% were males. The patients often had extensive coronary risk factors. The most prevalent clinical diagnosis was stable angina (36%), followed by myocardial infarction (MI) excluding acute myocardial infarction (AMI; 28%) and AMI (25%). Plain old balloon angioplasty was used as the sole procedure in 58% of lesions for which an attempt to heal was made, and coronary stent placement in 38%. Angiographic success was achieved in 92% of attempted lesions. Mortality, MI and emergency coronary artery bypass grafting (CABG) rates during the hospitalization were 2.6%, 2.0% and 0.7%, respectively. In-hospital mortality rate for AMI was 7.6%, whereas that for elective PCI in cases without AMI was 0.6%. The overall mortality for 1.8 years was 8%. Repeat PCI was performed for 35% and CABG for 6% during the follow-up period. In Japan, PCI was performed in patients with coronary artery disease and extensive risk factors, but a high rate of angiographic success was achieved. The rates of in-hospital mortality and emergency CABG were low in non-AMI patients, but the 1-year rate of repeat PCI was as high as 32%.

The Japanese Coronary Intervention Study (JCIS) has revealed that 17,667 coronary artery bypass grafting (CABG) procedures were performed at 477 facilities during 1997, and this report describes the demographic and clinical characteristics, treatment strategies, and the in-hospital and the long-term outcomes in patients treated with CABG in Japan. A total of 1,862 CABG cases, which corresponded to approximately 10% of the overall CABGs, were selected at random. The mean age was 65 years, and 76% of cases were males. The most prevalent clinical diagnosis was stable angina (54%), followed by myocardial infarction (MI) excluding acute myocardial infarction (AMI) (48%), unstable angina (25%), and AMI (5%). A large proportion of cases had multivessel coronary artery disease: 3-vessel disease (56%) and left main trunk disease (29%). The CABG procedures were emergency in 16%, and 93% of anastomotic sites were patent. In-hospital mortality and MI occurred in 5.1% and 3.5% of cases, respectively. The in-hospital mortality rate for emergency CABG was 12.0%, whereas that for elective CABG was 3.8%. The overall mortality rate during the follow-up period of 2.3 years was 10%. During the follow-up period, MI and angina occurred in 2% and 8% of cases, respectively. Percutaneous coronary intervention (PCI) was performed for 8%, and repeat CABG for 0.8%. In Japan, CABG was performed in patients with multivessel coronary artery disease with extensive risk factors. Angiographically determined success was achieved in 93% and the need for subsequent revascularization was relatively low.