Ryosuke Noda

Predicting the Need for an Implantable Cardioverter Defibrillator Using Cardiac Metaiodobenzylguanidine Activity Together with Plasma Natriuretic Peptide Concentration or Left Ventricular Function

Despite widespread use of implantable cardioverter defibrillators (ICDs), their cost and the fact that only a certain group of patients fully benefits from the devices require appropriate risk stratification of patients. This study investigated whether altered cardiac autonomic function is associated with the occurrence of ICD discharge or lethal cardiac events. Methods: Fifty-four ICD-treated patients were prospectively followed after assessment of cardiac metaiodobenzylguanidine (MIBG) activity, quantified as the heart-to-mediastinum ratio (HMR), plasma concentration of brain natriuretic peptide (BNP), and left ventricular ejection fraction (LVEF). Patients were divided into 2 groups based on the presence (group A, n = 21) or absence (group B, n = 33) of appropriate ICD discharge during a 15-mo period. Results: Group A had a significantly lower level of MIBG activity and a higher plasma BNP level than did group B. Univariate analysis revealed BNP level, any medication, and late HMR to be significant predictors, and multivariate analysis showed late HMR to be an independent predictor. An HMR of less than 1.95 with a plasma BNP level of more than 187 pg/mL or an LVEF of less than 50% had significantly increased power to predict ICD shock: positive predictive values, 82% (HMR + BNP) and 58% (HMR + LVEF); negative predictive values, 73% (HMR + BNP) and 77% (HMR + LVEF); sensitivities, 45% (HMR + BNP) and 67% (HMR + LVEF); and specificities, 94% (HMR + BNP) and 70% (HMR + LVEF). Conclusion: When combined with plasma BNP concentration or cardiac function, cardiac MIBG activity is closely related to lethal cardiac events and can be used to identify patients who would benefit most from an ICD.

Prognostic value of the Tei index combining systolic and diastolic myocardial performance in patients with acute myocardial infarction treated by successful primary angioplasty

Cardiac systolic (left ventricular ejection fraction) and diastolic (mitral inflow velocity pattern and/or mitral deceleration time) function were reported as predictors of clinical outcome or left ventricular remodeling in patients with acute myocardial infarction (AMI). Recently, a new index (Doppler-derived index combining systolic and diastolic myocardial performance; Tei index) for combined systolic and diastolic ventricular function has been reported to be a useful and convenient method for evaluation of global ventricular function. We therefore investigated the usefulness of the Tei index by echocardiography for evaluation of infarct size and clinical outcome in patients with AMI treated by successful primary angioplasty. We analyzed 10 age-matched control subjects and 43 consecutive patients with first AMI treated by successful primary angioplasty. The Tei index of the AMI patients was significantly greater than that of the control subjects (0.630 ± 0.106 vs 0.375 ± 0.036, P ≪ 0.0001). Also, the Tei index showed a significant positive correlation with peak creatine kinase values and 99mTc-tetrofosmin scores. Moreover, multiple logistic regression analysis showed that the Tei index ≫0.70 (P = 0.0313, odds ratio = 14.14) was the only significant explanatory factor for cardiac death or developed congestive heart failure. The Tei index combining systolic and diastolic myocardial performance reflects infarct size and might be a predictor of clinical outcome in patients with AMI treated by successful primary angioplasty.

Long-term follow-up after coronary stent implantation in patients with coronary artery disease.

Prospective randomized trials of coronary stenting in patients with coronary artery disease have shown a reduced incidence of cardiac events. However, little is known of the late outcome of patients treated with coronary stenting. The purpose of this study was to evaluate the rela tively long-term clinical outcomes (3 to 6 years) of patients treated with successful coronary stenting. The long-term clinical outcome was studied in 101 consecutive patients (78 males and 23 females) who had undergone successful coronary stent implantation for coronary artery disease in our hospital from October 1994 to September 1997. During a follow-up period of 48.9 ±9.5 months (range, 6-73 months), cardiac events were documented in 37 patients. The rate of survival free of cardiac events was 67% at 3 years. Multiple logistic regression analysis showed that ACC/AHA lesion type and residual percent diameter stenosis greater than 20% after stenting were the significant explanatory factors of adverse cardiac events. Long-term clinical outcome in patients with coronary artery disease treated with successful coronary stenting was influenced by the ACC/AHA lesion type of stented lesion and residual percent diameter stenosis after stent implantation.

Cardiac imaging in a patient with anomalous origin of the left coronary artery from the pulmonary artery: a case report

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is an uncommon congenital heart disease and has a high mortality rate in infancy. However, myocardial ischemia does not develop until adolescence or adulthood in about 10% of patients. Moreover, the diagnosis of ALCAPA is often difficult in cases without heart murmur or cardiac symptoms. The authors report the case of a 31-year-old man with ALCAPA. He was admitted to the hospital for evaluation of mild shortness of breath at exercise, but he had no typical chest symptoms due to myocardial ischemia or heart failure until age 31 and he had no heart murmur. Moreover, electrocardiogram did not show an old myocardial infarction or myocardial ischemia. Therefore, the authors did not suspect ALCAPA until they performed transthoracic echocardiography and exercise-stress single photon emission computed tomography (SPECT) with Tc-99m-tetrofosmin. The final diagnosis was established from the results of coronary arteriography. In the present case, a transthoracic echocardiogram showed abnormal coronary circulation, and exercise-stress SPECT revealed reversible myocardial ischemia. Transthoracic echocardiography and myocardial SPECT imaging could be a useful noninvasive tools for diagnosing the ALCAPA.