Significant dependency of left atrial strain on left ventricular longitudinal motion.

BACKGROUND: The effects of left ventricular longitudinal function on the left atrial strain, including the left atrial reservoir function, have not been adequately quantified. METHODS: A total of 124 patients who underwent echocardiography were enrolled in this study. Left atrial strain analysis was performed using two-dimensional speckle tracking echocardiography, and the left atrial volume was derived using the modified Simpson's method. The peak left atrial strain (LAS) and left atrial expansion index (LAEI), as indices of left atrial reservoir function, were measured. The global longitudinal strain (GLS) and mitral annular plane systolic excursion (MAPSE), which are indices of contractile motion toward the left ventricular apex, were also measured. The correlation between LAS and candidate determinants, including left ventricular systolic longitudinal function, was evaluated, and multivariate regression analysis was performed. RESULTS: A significant correlation was found between LAS and left ventricular systolic longitudinal functions, GLS (r = 0.63, p < 0.001), and MAPSE (r = 0.65, p < 0.001). Two models, which were selected by multiple regression analyses for LAS, included GLS or MAPSE as independent determinants. GLS and MAPSE were also the strongest predictors, among other factors. CONCLUSION: LAS, when determined by evaluating the left atrial reservoir function, was significantly associated with left ventricular function, especially the systolic longitudinal function. Left ventricular function should be considered when assessing left atrial function by LAS.

Importance of left ventricular contraction for left atrial reservoir function.

BACKGROUND: The determinants of left atrial (LA) reservoir function have not been clarified. METHODS: To elucidate the effect of left ventricular (LV) contraction on LA reservoir volume (ΔVLA), volume change due to mitral annular downward motion and aortic root anterior motion, which are related to LV contraction during systole, was calculated in 72 consecutive subjects [42 patients without any cardiac disease (control group), 13 patients with heart failure with reduced ejection fraction (HFrEF group) and 17 with preserved ejection fraction (HFpEF group)]. LA volume was calculated using the modified Simpson's method of bi-plane 2-D echocardiograms. ΔVLA was the difference between the maximum and minimum LA volumes. LA volume change according to mitral annular motion (ΔVMA) and aortic root motion (ΔVAR) were calculated by assuming an oval frustum and dented wedge, respectively. RESULTS: In the normal control group, ΔVAR + ΔVMA was 11.7 ml on average, correlating to ΔVLA (r = 0.55, p < 0.01), and the contribution rate to LA reservoir volume ((ΔVAR + ΔVMA)/ΔVLA) was 56% on average. In both, the HFrEF and HFpEF groups, ΔVAR, ΔVMA, and the contribution rate were significantly smaller than those in normal control group. Stroke volume correlated to ΔVAR and ΔVMA. The larger the maximum LA volume was, the smaller the contribution rate was. The smaller the rate was, the higher the systolic pulmonary artery pressure was. CONCLUSIONS: Both mitral annular motion and aortic root anterior motion, which are related to ventricular contraction, are important for the LA reservoir volume recruitment.

Left ventricular cardiac hemangioma in a patient with chronic heart failure.

Cardiac hemangiomas are rare benign tumors. Here, we report the case of a man in his 30s who had a cardiac hemangioma with no symptoms. He was being treated with ß-blockers for chronic heart failure with hypertensive heart disease at Osaka Minato Central Hospital. Routine echocardiography revealed a mobile spherical mass in the left ventricle that had not been detected on echocardiography performed 4 months previously. Subsequently, the tumor was excised to prevent potential embolic events and was pathologically diagnosed as a cardiac hemangioma. This case demonstrates the relatively rapid progress of a cardiac hemangioma regardless of ß-blocker administration, which is occasionally used for the treatment of hemangiomas. The efficacy of ß-blockers in treating cardiac hemangiomas may vary according to the type of ß-blocker. Echocardiography is useful in screening and follow-up of cardiac hemangiomas; however, additional imaging modalities are needed for differential diagnosis.

Successful catheter ablation to accessory atrioventricular pathway as cardiac resynchronization therapy in a patient with dilated cardiomyopathy.

A 55-year-old man was admitted to our hospital for further examination of the abnormalities of chest X-ray and electrocardiogram. He was diagnosed with type B Wolff-Parkinson-White syndrome concomitant with dilated cardiomyopathy. Despite the medical therapy using enalapril and carvedilol for 20 months, his cardiac performance and brain natriuretic peptide (BNP) were not so improved. Because asynchronous septal motion caused by pre-excitation through a right-sided accessory pathway (AP) might deteriorate his cardiac performance, catheter ablation to the AP was performed. Successful procedure after 17 months improved left ventricular (LV) contraction, reduced LV volume, and decreased mitral regurgitation and BNP.

Usefulness of plasma brain natriuretic peptide concentration for predicting subsequent left ventricular remodeling after coronary angioplasty in patients with acute myocardial infarction.

To determine the relation between plasma brain natriuretic peptide (BNP) and remodeling in terms of infarct-related artery (IRA) patency, 106 patients with a first anterior wall acute myocardial infarction with a patent IRA at 1 month were studied. The IRA reoccluded at 6 months in 17 patients (reoccluded IRA) and was patent in 89 patients (patent IRA). The 2 groups did not differ with respect to clinical characteristics, hemodynamic variables, and left ventricular function at 1 month, except for left ventricular end-diastolic and systolic volumes, which were significantly greater in the reoccluded IRA group. Plasma BNP concentration in the reoccluded IRA group (336 +/- 288 pg/ml) was significantly higher than that in the patent IRA group (116 +/- 106 pg/ml) at 1 month. BNP concentration decreased significantly at 6 months in the 2 groups (reoccluded IRA vs patent IRA 152 +/- 162 vs 44 +/- 58 pg/ml, p <0.05). The increase in left ventricular volume from 1 to 6 months was significantly correlated with plasma BNP concentration at 1 month in the patent IRA group (r = 0.314, p < 0.01) and the reoccluded group (r = 0.634, p < 0.01). Linear regression analysis showed that the correlation between the 2 parameters in the 2 groups was similar. Based on stepwise multivariate linear regression analysis, only plasma BNP concentration was significantly correlated with the increase in left ventricular volume from 1 to 6 months in the 2 groups. In conclusion, these results suggest that plasma BNP concentration predicts left ventricular dilation independently of IRA patency.

Anomalous right coronary artery originating from the distal left circumflex artery: single coronary artery with choronic atrial fibrillation.

This report describes a patient with a single coronary artery in whom the right coronary artery originated from the distal left circumflex artery. Single coronary artery is a rare congenital anomaly of the coronary circulation which is often associated with other congenital cardiac malformations. This anomaly is thought to be clinically significant especially in patients with atrial fibrillation, although no other associated cardiac anomaly was detected.

Twice-daily administration of a long-acting angiotensin-converting enzyme inhibitor has greater effects on neurohumoral factors than a once-daily regimen in patients with chronic congestive heart failure.

Although many clinical trials have evaluated the use of long-acting angiotensin-converting enzyme (ACE) inhibitors in patients with chronic congestive heart failure (CHF), there are no data regarding whether a once-daily or twice-daily regimen is preferable with respect to effects on the neuroendocrine system. To address this issue, the authors evaluated the comparative effects of the administration schedule on neurohumoral factors and autonomic nervous activity in patients with CHF. Thirty-two patients with mild compensated CHF received lisinopril (5-20 mg/d) orally either once a day (n = 17) or twice a day (n = 15) for more than 3 months. After this initial therapy, patients receiving a once-daily regimen switched to a twice-daily regimen and vice-versa, and patients were followed for an additional 3 months. Neurohumoral factors and the coefficient of variance in the electrocardiographic R-R interval (CVRR) were measured. Hemodynamic parameters, renal function, plasma concentrations of brain natriuretic peptide and aldosterone, and CVRR did not differ between the two regimens. However, the plasma concentration of norepinephrine was significantly lower, and plasma renin activity tended to be lower with the twice-daily regimen. These findings suggest that twice-daily administration of long-acting ACE inhibitors may have better effects on the neuroendocrine system than a once-daily regimen in patients with mild CHF.

Analysis of transmural trends in myocardial integrated backscatter in patients with progressive systemic sclerosis.

Cardiac involvement in progressive systemic sclerosis (PSS) is common and has a strong negative impact on the prognosis, especially when autoantibodies are present. To determine whether ultrasonic tissue characterization can detect early ultrastructural changes in the sclerodermal myocardium, we analyzed the transmural heterogeneity in myocardial integrated backscatter (THIB). "A-THIB" was defined as the absolute difference in integrated backscatter between the left (subendocardial) and right (subepicardial) ventricular halves of the myocardium in the septum and posterior wall, and was measured in 11 patients with PSS and 10 age- and sex-matched healthy participants. A-THIB in patients with PSS was higher than that in healthy participants (1.3 +/- 1.3 vs 4.0 +/- 1.4 dB for the septum and 1.1 +/- 0.7 dB vs 2.8 +/- 0.4 dB for the posterior wall; mean +/- SD, respectively, P <.0005). Septal A-THIB was higher in patients with PSS with than without anti-Scl70 or antinucleolar antibodies (3.2 +/- 1.1 vs 5.0 +/- 1.0 dB, P =.0165). Early changes in the myocardium of patients with PSS, possibly related to increased interstitial collagen deposition, can be detected by quantitative analysis of THIB.

Comparison of time of reperfusion during anterior wall acute myocardial infarction to left ventricular volume one month and 20 months later.

We studied 95 patients with a first anterior wall acute myocardial infarction who received successful reperfusion within 72 hours after the onset. The patients were divided into 4 groups based on the time required to achieve reperfusion; <3 hours (n = 23), 3 to 6 hours (n = 42), 6 to 24 hours (n = 17), and >24 to 72 hours (n = 13). The infarct size, as evaluated by thallium-201 single-photon emission computed tomography, at 1 month after the infarct was significantly larger (p <0.05) in >24 to 72 hours (1,593 +/- 652 U) than that in <3 hours (749 +/- 650 U), but was not significantly different from that at 3 to 6 hours (1,353 +/- 770 U) or 6 to 24 hours (1,371 +/- 561 U). The end-diastolic volume index at 1 month did not differ among the 4 groups. However, the end-diastolic volume index during the follow-up period (20 +/- 8 months) in >24 to 72 hours (93 +/- 23 ml/m(2)) was significantly larger than that in the other 3 groups (<3 hours [65 +/- 21 ml/m(2)], 3 to 6 hours [65 +/- 22 ml/m(2)], and 6 to 24 hours [70 +/- 25 ml/m(2)]). Similar findings were observed in end-systolic volume index. In conclusion, although infarct size reduction was not observed by late reperfusion, left ventricular volumes at 1 month were comparable among patients with successful reperfusion within 3 and up to >24 hours. Left ventricular volumes 2 years after acute myocardial infarction were significantly larger in patients who did not under reperfusion for >24 hours.