Takashi Touma

Impact of high coronary artery calcification score (CACS) on survival in patients on chronic hemodialysis

BackgroundElectron-beam computed tomography (EBCT) is a noninvasive measure of coronary artery calcification and, therefore, could be a marker of developing cardiovascular disease. Whether the coronary artery calcification score (CACS) is a prognostic marker in chronic dialysis patients is not known.MethodsIn the present study, the mortality rate was observed in relation to the baseline CACS. EBCT was performed in 104 chronic hemodialysis patients (62 men and 42 women) in one dialysis unit. The mean (SD) duration of hemodialysis was 48.7 (62.6) months at the time of EBCT. The mean (SD) age at EBCT was 55.9 (13.6) years, ranging from 23 to 88 years. The duration of follow-up was 43.8 (19.3) months after the EBCT. Cox proportional hazard analysis was performed to examine the impact of CACS on survival after adjusting for age, sex, duration of dialysis, diabetes mellitus, hypertension, serum albumin, and dyslipidemia.ResultsThe CACS was distributed from zero to 5896, with a median of 200. During the study period, 24 patients (15 men and 9 women) died, 7 in the low CACS group (≪200) and 17 in the high CACS group (≧200). The 5-year cumulative survival rate was 84.2% in the low CACS group and 67.9% in the high CACS group. The adjusted relative risk (95% confidence interval) of death was 1.001 (1.000–1.002); P = 0.0003, for the absolute value of CACS.ConclusionsThe present study suggested that CACS was an independent predictor of death in patients on chronic hemodialysis. Patients with a high CACS should be carefully monitored and evaluated for reversible prognostic factors such as dyslipidemia and, probably, hyperphosphatemia and a high value for the calcium × phosphate product.

Usefulness of Leg-Crossing for Maintaining Blood Pressure in a Sitting Position in Patients with Orthostatic Hypotension—Case Reports

The authors report a case with idiopathic orthostatic hypotension in which the patient prevents his blood pressure from fatting to a symptomatic level by leg-crossing in a sitting position. Including 4 other patients with orthostatic hypotension and 5 normal subjects, their study found that the changes in blood pressure with leg-crossing inversely correlated with those induced by assuming seated posture from a supine position. Leg-crossing may, therefore, be one of the useful nonpharmacologic measures for maintaining blood pressure in a sitting position in patients with orthostatic hypotension.

MILD MENTAL STRESS INCREASES INSULIN SENSITIVITY IN HEALTHY YOUNG MEN

We examined if mental stress alters insulin sensitivity and renal sodium handling in 11 normotensive young men. Following a 60-minute period of equilibration, we performed euglycemic hyperinsulinemic glucose clamp for 150 minutes. The clamp period was divided into three phases; control phase for 90 minutes (I), mental arithmetic phase for 30 minutes (II), and recovery phase for 30 minutes (III). Blood pressure, heart rate and glucose disposal rate (M value) significantly elevated during phase II of the stress study. In a time control study, in which mental arithmetic was not loaded during phase II, blood pressure was kept constant and the changes in M value from phase I to phase II were significantly smaller than those in the stress study. In both studies, fractional excretion of sodium did not significantly change throughout the study period. Thus, insulin sensitivity concerning glucose metabolism increased in response to mild mental stress. However, the effect of insulin on sodium handling was not altered by the stress.

Rescue Balloon Pulmonary Angioplasty Under Veno-Arterial Extracorporeal Membrane Oxygenation in a Patient With Acute Exacerbation of Chronic Thromboembolic Pulmonary Hypertension

We describe a case of a 41-year-old woman with acute exacerbation of chronic thromboembolic pulmonary hypertension (CTEPH) complicated by rapidly progressive respiratory failure and right heart failure with cardiogenic shock. A computed tomography (CT) showed thrombi in the right main pulmonary artery and bilateral peripheral pulmonary arteries, and echocardiography showed right ventricular dilatation and tricuspid regurgitation, with an estimated pressure gradient of 80 mmHg. The patient was initially diagnosed with acute pulmonary thromboembolism, and thrombolytic therapy was administered. Her condition subsequently deteriorated, however, necessitating mechanical ventilation and veno-arterial extracorporeal membrane oxygenation (VA-ECMO). We performed emergency catheter-directed thrombectomy and thrombus aspiration. Pulmonary hypertension (PH) temporarily improved, but subsequently worsened, and the patient was diagnosed with CTEPH. Pulmonary endarterectomy (PEA) was performed. After PEA, we were unable to wean the patient off VA-ECMO, and rescue balloon pulmonary angioplasty (BPA) to the middle and inferior lobe branches of the right lung was performed. Five days after BPA, the patient was removed from VA-ECMO and on the 57th day of hospitalization, she was weaned off the ventilator. The patient was discharged after 139 days of hospitalization. Rescue BPA represents a useful intervention for improving PH and weaning off VA-ECMO in a patient with acute exacerbation of CTEPH.

Chronic Hypovolemia Associated with Accelerated Hypertension and Orthostatic Hypotension in a Patient on Continuous Ambulatory Peritoneal Dialysis

We report a patient with nondiabetic end-stage renal disease on continuous ambulatory peritoneal dialysis (CAPD) associated with chronic hypovolemia. Despite the administration of nilvadipine, the patient showed accelerated hypertension and concomitantly orthostatic hypotension. Plasma renin activity was markedly high, and blockade of angiotensin II action by captopril or an angiotension II antagonist decreased the supine blood pressure. This indicated that the enhanced activity of the renin-angiotensin system was the principal cause of the supine hypertension. The plasma concentration of norepinephrine was also very high. After correction of hypovolemia by blood transfusion, the enhancement of the renin-angiotensin system and high plasma norepinephrine level were reduced, and symptomatic orthostatic hypotension disappeared. The accelerated hypertension was easily controlled by the administration of low-dose captopril and nilvadipine. These findings suggest that chronic hypovolemia related to the intractable supine hypertension as well as orthostatic hypotension. Hypovolemia-induced enhancement of the renin-angiotensin system and sympathetic nerve activity may cause vasoconstrictive hypertension in patients on CAPD.

A Case of Refractory Heart Failure in Becker Muscular Dystrophy Improved With Corticosteroid Therapy

The patient was a 26 year-old man who was referred to our hospital in June 2011 because of severe heart failure. At age 24 years, he was found to have Becker muscular dystrophy. He received enalapril for cardiac dysfunction; however, he had worsening heart failure and was thus referred to our hospital. Echocardiography showed enlargement of the left ventricle, with a diastolic dimension of 77 mm and ejection fraction of 19%. His condition improved temporarily after an infusion of dobutamine and milrinone. He was then administered amiodarone for ventricular tachycardia; however, he subsequently developed hemoptysis. Amiodarone was discontinued and corticosteroid pulse therapy was administered followed by oral prednisolone (PSL). His creatinine phosphokinase (CPK) level and cardiomegaly improved after the corticosteroid therapy. The PSL dose was reduced gradually, bisoprolol was introduced, and the catecholamine infusion was tapered. A cardiac resynchronization device was implanted; however, the patients condition gradually worsened, which necessitated dobutamine infusion for heart failure. We readministered 30 mg PSL, which decreased the CPK level and improved the cardiomegaly. The dobutamine infusion was discontinued, and the patient was discharged. He was given 7.5 mg PSL as an outpatient, and he returned to normal life without exacerbation of the heart failure. There are similar reports showing that corticosteroids are effective for skeletal muscle improvement in Duchenne muscular dystrophy; however, their effectiveness for heart failure has been rarely reported. We experienced a case of Becker muscular dystrophy in which corticosteroid therapy was effective for refractory heart failure.