A case of coronary artery fistula diagnosed in the right decubitus position by transthoracic echocardiography.

A 70-year-old woman was admitted to our hospital for a continuous heart murmur in the fourth intercostal space at the right sternal border. Routine echocardiography demonstrated aneurismal dilatation at the origin of right coronary artery. These findings suggested a coronary artery fistula, although its drainage site could not be identified. By shifting the patient to the right decubitus position, we could observe an abnormal color Doppler signal going from the right coronary artery into the right atrium, confirming coronary artery fistula. The right decubitus position may be helpful for the evaluation of abnormal anatomic and auscultatory findings.

Interatrial septum pacing decreases atrial dyssynchrony on strain rate imaging compared with right atrial appendage pacing.

BACKGROUND: Interatrial septum pacing (IAS-P) decreases atrial conduction delay compared with right atrial appendage pacing (RAA-P). We evaluate the atrial contraction with strain rate of tissue Doppler imaging (TDI) during sinus activation or with IAS-P or RAA-P. METHODS: Fifty-two patients with permanent pacemaker for sinus node disease were enrolled in the study. Twenty-three subjects were with IAS-P and 29 with RAA-P. The time from end-diastole to peak end-diastolic strain rate was measured and corrected with RR interval on electrocardiogram. It was defined as the time from end-diastole to peak end-diastolic strain rate (TSRc), and the balance between maximum and minimum TSRc at three sites (ΔTSRc) was compared during sinus activation and with pacing rhythm in each group. RESULTS: There were no significant differences observed in general characteristics and standard echocardiographic parameters except the duration of pacing P wave between the two groups. The duration was significantly shorter in the IAS-P group compared with the RAA-P group (95 ± 34 vs 138 ± 41; P = 0.001). TSRc was significantly different between sinus activation and pacing rhythm (36.3 ± 35.7 vs 61.6 ± 36.3; P = 0.003) in the RAA-P group, whereas no significant differences were observed in the IAS-P group (25.4 ± 12.1 vs 27.7 ± 14.7; NS). During the follow-up (mean 2.4 ± 0.7 years), the incidence of paroxysmal atrial fibrillation (AF) conversion to permanent AF was not significantly different between the two groups. CONCLUSIONS: IAS-P decreased the contraction delay on atrial TDI compared to RAA-P; however, it did not contribute to the reduction of AF incidence in the present study.

Long-term effect of spironolactone on cardiac structure as assessed by analysis of ultrasonic radio-frequency signals in patients with ventricular hypertrophy.

BACKGROUND: An effect of aldosterone on ventricular fibrosis has been demonstrated in animals, but remains unclear in human patients. This study aimed to investigate (1) the relationship between left ventricular (LV) fibrosis and myocardial ultrasonic texture as assessed with myocardial radio-frequency (RF) signals analyzed from the viewpoint of their waveform with chaos theory in animals and (2) serial changes in myocardial ultrasonic texture following long-term aldosterone blockade in patients with LV hypertrophy. METHODS AND RESULTS: In an animal study, Sprague-Dawley rats were divided into 2 groups with and without adriamycin administration, and the relationship between the RF signals and LV fibrosis was assessed. In a clinical study, effects of 12-month-administration of spironolactone were assessed in patients with LV hypertrophy. The animal study revealed that the correlation dimension (CD) calculated from the RF signals inversely correlated with the area of fibrosis. The clinical study demonstrated an increase in CD following 6-month administration of spironolactone. The changes in CD positively correlated with those in the serum carboxy-terminal telopeptide of collagen type I. CONCLUSION: Myocardial RF signals analyzed with chaos theory reflect the severity of LV fibrosis. Aldosterone blockade may alter myocardial ultrasonic texture with regression of LV fibrosis, at least partly through enhanced collagen degradation.

Instantaneous assessment of left ventricular midwall mechanics with tissue Doppler tracking technique.

BACKGROUND: Left ventricular (LV) systolic function is better characterized by midwall mechanics in patients with LV hypertrophy than by endocardial LV function, and the midwall mechanics is an independent predictor of prognosis. However, a complex calculation is currently required to assess it, and it is not routinely assessable in clinical practice. Tissue Doppler imaging enables tracking of a point within the LV wall though a cardiac cycle; we tested our hypothesis that the tissue Doppler tracking technique provides an instantaneous and reliable evaluation of midwall mechanics. METHODS: LV M-mode echocardiogram was recorded in 18 subjects with conventional echocardiography and with tissue Doppler imaging. The midwall shortening was calculated from the data obtained with conventional echocardiography for the comparison with that measured with the tissue Doppler tracking technique. The tissue Doppler-determined midwall shortening correlated well with conventionally calculated value (r=.84, P<.0001), and their difference was small irrespective of absolute value of the midwall shortening. CONCLUSIONS: The midwall mechanics can be instantaneously and accurately evaluated with the tissue Doppler tracking technique.