Successful resynchronization by permanent His-bundle pacing in a patient with pacing-induced cardiomyopathy.

Right ventricular (RV) pacing has been reported to result in ventricular dyssynchrony, heart failure, and increased mortality. Pacing associated deterioration of left ventricular (LV) systolic function has been termed pacing-induced cardiomyopathy (PICM). While upgrading to biventricular pacing (BiVP) is an effective therapy for PICM, permanent His-bundle pacing (HBP) can be a physiological alternative to BiVP. We present a patient with PICM who responded dramatically to permanent HBP.

Current status of lipid management of hypertensive patients.

Hypertensives, in addition to requiring strict blood pressure control, need lipid management to prevent cardiovascular disease. To assess the current status of lipid management of hypertensives, we reviewed the profiles of 830 hypertensives. The quality of lipid management was assessed using the Japan Atherosclerosis Society (JAS) Guideline for Diagnosis and Treatment of Hyperlipidemia in Japanese Adults announced in 1997. Hyperlipidemia was diagnosed in 45.2% of hypertensives and in 56.6% of patients in category C (a group of patients with coronary heart disease). Lipid-lowering drugs were used in 63.5% of all hypercholesterolemic patients and in 78.1% of category C patients. Statins were administered to more than 80% of hypercholesterolemic patients. Only 39.4% of hypertensives achieved the target total cholesterol level and only a very small percentage (17.1%) of patients in category C reached the target levels. The elderly hypertensives were the single largest group (42.2% of all hypertensives) in this study population, and the target cholesterol level for this group has been elevated from 200 mg/dl to 220 mg/dl in the JAS Guidelines for Diagnosis and Treatment of Atherosclerotic Cardiovascular Diseases announced in 2002 (new guidelines). In conclusion, in hypertensives requiring lipid management, the lipid-lowering approach appeared insufficient, as the target achievement rate was relatively low despite a high treatment rate. This was most marked for patients in category C.

The status of hypertension management in Japan in 2000.

To evaluate the current status of the management of hypertensive patients in Japan, we investigated 907 treated hypertensive patients (486 females and 421 males; mean age, 66.7 years) followed by cardiologists. According to the guidelines for the management of hypertensive patients in Japan in 2000 (JSH-2000), only 41.5% of the subjects achieved the target blood pressure, with a mean systolic blood pressure of 140.0+/-14.9 mmHg and a mean diastolic blood pressure of 80.0+/-10.7 mmHg. There were no differences between patients with and without concurrent disease or among age groups (<60, 60-69, 70-79, and 80 years and over) in systolic blood pressure levels achieved. However, the diastolic blood pressure decreased with age, indicating an increase of the pulse pressure. Overall, the prescription rates were: calcium channel blockers (CCBs), 73.0%; angiotensin converting enzyme inhibitors (ACE-inhibitors), 31.3%; angiotensin receptor blockers (ARBs), 18.9%; beta-blockers, 16.2%; and diuretics, 10.1%. Although some selection of antihypertensive drugs was based on evidence from previous trials on hypertensive patients with diabetes mellitus, chronic heart failure and renal insufficiency, overall, CCBs were selected in all age groups and in all comorbid conditions. In conclusion, Japanese cardiologists do not appear to consider age and comorbidity when choosing antihypertensive managements. Based on current evidence, the management of hypertension should be individualized, with the blood pressure target level and antihypertensive medications chosen on the basis of age and comorbidity.

L-cysteine prevents oxidation-induced block of the cardiac Na+ channel via interaction with heart-specific cysteinyl residues in the P-loop region.

The present study investigated the protective effects of L-cysteine on the oxidation-induced blockade of Na+ channel a-subunits, hH1 (cardiac) and hSkM1 (skeletal), expressed in COS7 cells. Na+ currents were recorded by the whole-cell patch clamp technique (n = 3-7). L-cysteine alone blocked hH1 and hSkM1 in a dose-dependent manner, with saturating L-cysteine block at 3,000 micromol/L. Hg2+, a potent sulfhydryl oxidizing agent, blocked hH1 with a time to 50% inhibition (Time50%) of 20s. Preperfusion of COS7 cells with 100 micromol/L L-cysteine significantly slowed the Hg2+ block of hH1 (Time50% = 179 s). L-cysteine did not prevent Hg2+ block of hSkM1 (Time50% = 37s) or the C373Y hH1 mutant (Time50% = 43s). As for other sulfo-amino acids, homocysteine prevented the Hg2+ block of hH1, with the Time50% (70s) being significantly smaller than that of L-cysteine, whereas methionine did not prevent the Hg2+ block of hH1. L-cysteine did not prevent the Cd2+ block of hH1. These results indicate that L-cysteine selectively acts on heart-specific Cys373 in the P-loop region of hH1 to prevent Cys373 from the oxidation-induced sulfur-Hg-sulfur bridge formation.