Journal of cardiography最新文献

ECG-gated magnetic resonance imaging (MRI) was performed for healthy volunteers and for patients with various heart diseases, and its usefulness was compared with that of two-dimensional echocardiography. For this study, several modifications were made in the MRI equipment used. First, a surface coil was introduced for recording the MR signal, resulting in a high S/N ratio. Second, an oblique scan mode was developed for selecting freely the slices similar to those chosen by two-dimensional echocardiography. For imaging, the back projection method and spin echo (SE) pulse sequence were chosen to minimize motion artifacts caused by cardiac beats. In this study, left ventricular wall thickness and left ventricular volume were estimated from gated MR images, taken both in the horizontal and oblique longitudinal scan modes. The results were as follows: The anterior, inferior and apical left ventricular walls were clearly visualized with oblique longitudinal scan images. The thickness of the interventricular septum and posterior wall were measured on left ventricular horizontal scan images. Each measurement was compared with data obtained by two-dimensional echocardiography. Both correlation factors were about 0.70, indicating poor correlations. Left ventricular ejection fraction was calculated from left ventricular volume estimates. Comparison of left ventricular ejection fractions estimated by MRI and two-dimensional echocardiography revealed a close similarity. We concluded that MRI is useful for non-invasive evaluation of cardiac function, and in detecting wall thickness abnormalities due to various heart diseases.

A new computer system was proposed to evaluate abnormal motion of the ventricular wall in patients with myocardial infarction. Multi-slice ECG-gated cardiac X-ray CT (MSECT), a new technique developed in our laboratory, was the source of the original image. Using this system, we reconstructed three-dimensional images, calculated % shortening values of the entire heart, and visualized abnormal wall motion on the ventricular surface, displaying three-dimensionally. Our initial study of five patients with myocardial infarction showed good correlation between the findings using this system and conventional echocardiography and cine-ventriculography. Since the development of the ECG-gated method, the application of CT to the study of heart diseases has progressed rapidly. In patients with myocardial infarction, ECG-gated cardiac CT is used to visualize infarcted myocardium and to evaluate impaired cardiac function. However, such analyses were limited to single slices, because a large dose of contrast medium was required to distinguish the ventricular chamber from the myocardium. By adopting multi-slice ECG-gated cardiac X-ray CT images as the data source and using three-dimensional reconstruction technique, this system is useful for evaluating abnormal wall motion.

Left ventricular end-diastolic pressure (LVEDP) was estimated noninvasively using cardiac parameters obtained from simultaneous recordings of the echocardiograms, electrocardiograms and phonocardiograms in 30 patients who underwent diagnostic left cardiac catheterization. Special attention was paid to the mitral valve motion which reflects global left ventricular function. The interval from the onset of the Q wave of the ECG to the echocardiographic C point of mitral valve closure (Q-C), the interval from the aortic component of the second heart sound to the E point of the mitral echogram (IIa-E), and the time from the opening of the mitral valve (D point) to the E point (D-E) were measured. A good correlation with LVEDP was observed with Q-C/IIa-E (r = 0.87, p less than 0.001), and inversely with D-E time (r = -0.81, p less than 0.001). The correlation of Q-C/D-E and LVEDP was most significant (r = 0.89, p less than 0.001). The regression equations were LVEDP = 36.6 X (Q-C/IIa-E) -10.9 and LVEDP = 4.49 X (Q-C/D-E) +5.56. This noninvasive and easily repeated method for predicting LVEDP is very useful clinically.

A two and a half year follow-up study of segmental left ventricular wall motion was performed by two-dimensional echocardiography for 26 patients with dilated cardiomyopathy (DCM). Segmental analysis of left ventricular wall motion abnormalities (WMA) was performed using 11 segments obtained by short- and long-axis views of the left ventricle. Wall motion in each segment was classified and assigned a numerical score as normal (0), hypokinetic (1), severely hypokinetic (2), and akinetic or dyskinetic (3). Based on this categorization, a wall motion abnormality index (WMAI) was derived as an overall assessment of left ventricular asynergy. The intersegmental standard deviation of the wall motion abnormality score was used as an index of left ventricular asynergy (non-uniformity index: NUI). During the follow-up period, the wall motion abnormality index increased in all of the 26 patients (from 1.23 to 1.82, p less than 0.001), but the non-uniformity index did not change (from 0.72 to 0.73). When comparing the non-uniformity index among three groups classified according to the grade of wall motion abnormality, both at the initial and during follow-up studies, the moderate wall motion abnormality group (1.0 less than or equal to WMAI less than 2.0) had larger non-uniformity indexes (0.83, 0.84) than the other groups, and the severe non-uniformity index (greater than or equal to 0.9) was observed solely in the moderate group. In the follow-up study, these 26 patients were categorized in two groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Twenty-one members of a family were traced for three generations including the propositus, who had typical dilated cardiomyopathy (DCM)-like features. Clinical, radiological, electrocardiographic and echocardiographic examinations were performed for 13 of 16 still living. Five of 21 members died including three of sudden death. Among living 16 members, five had congestive heart failure, greater than grade III of the NYHA, and cardiomegaly on chest radiography in five. Left ventricular hypertrophy, abnormal Q waves, and ST-T changes were observed on electrocardiography in two, five and eight members, respectively. Echocardiography revealed asymmetric septal hypertrophy (ASH) in four, two of whom had systolic anterior motion (SAM) of the mitral valve. Two had features simulating DCM, and five had mitral valve prolapse. Among six patients with ASH or features simulating DCM, four had cardiac catheterization, coronary angiography and endomyocardial biopsy. None had significant coronary stenosis, but all had high left ventricular end-diastolic pressure (LVEDP) (23 +/- 7 mmHg). Endomyocardial biopsy showed moderate myocardial cellular hypertrophy, interstitial myocardial fibrosis, nuclear changes and myocardial disarrangement, with features characteristic of HCM. In this family with malignant HCM, patients had various clinical features including typical HCM, simulated DCM, DCM coexisted with mitral valve prolapse, and sudden death occurred frequently.

To assess the prosthetic aortic valve functions according to types and sizes of valves, the peak flow velocity was recorded by means of continuous wave Doppler echocardiography in 40 patients (age 45 +/- 15 years) with prosthetic aortic valves and in 25 normal subjects. Twenty-one patients had Björk-Shiley valves (1-18 months after replacement); 12 had St. Jude Medical valves (6-48 months after replacement); and seven had Carpentier-Edwards porcine xenografts (48-84 months after replacement). The peak blood flow velocity across the prosthetic valve was recorded at the left ventricular apex, the suprasternal notch, and the right parasternal border in the second intercostal space. The pressure gradient was derived from the peak flow velocity by means of the simplified Bernoulli equation (P = 4V2). The peak and mean flow velocities and the peak and mean pressure gradients were measured to evaluate the opening function of the prosthetic valves. The results were as follows; The peak flow velocities were recorded in 33 patients (83%) with aortic valve replacements. All four measurements were significantly greater in patients with prosthetic aortic valves than in normal subjects, but there was no significant difference according to the valve type. The opening function was less in patients with smaller valves than in those with larger ones. There was a clear correlation between opening function and valve size. We concluded that continuous wave Doppler echocardiography is a useful noninvasive method for evaluating the opening function of a prosthetic aortic valve.

This is a report of a patient with mitral valve prolapse (MVP) and myocardial abnormalities on endomyocardial biopsy in whose relatives hypertrophic cardiomyopathy (HCM) was identified. A 19-year-old woman was admitted to our hospital for evaluation of a heart murmur. A systolic ejection murmur was audible in the third intercostal space at the left sternal border, and a standard 12-lead electrocardiogram showed ST-T wave changes in leads II, III and aVF. Echocardiography revealed prolapse of the anterior leaflet of the mitral valve, but no left ventricular hypertrophy. Endomyocardial biopsy disclosed mild hypertrophy and disarrangement of the myocardium. The family study revealed asymmetrical septal hypertrophy in her mother, who had no history of hypertension. Her younger sister had mild hypertrophy of the interventricular septum on echocardiography, and her histopathological findings suggested a diagnosis of HCM. This case was clinically regarded as MVP, but development of left ventricular hypertrophy as noted in her mother may occur in the future.

To study the "reversed Hegglin syndrome" in Takayasu arteritis, 57 patients were selected, and divided into four groups; Group I: 12 with Takayasu arteritis with aortic regurgitation (AR), Group II: 27 with Takayasu arteritis without AR, Group III: six with annuloaortic ectasia and severe AR, and Group IV: 12 with severe AR of other miscellaneous etiologies. QII-QT intervals were compared among the four groups. The reversed Hegglin syndrome (QII-QT greater than or equal to 40 msec) was observed in 58 percent of Group I patients and 37 percent of Group II patients. This phenomenon was not seen in any patients in Group III or IV. Sixteen of the 17 patients who had the reversed Hegglin syndrome belonged to the thoracic aortic type or diffuse type of Takayasu arteritis. Most patients who did not have this syndrome either had a localized lesion or a prolonged QT interval. The reversed Hegglin syndrome, therefore, is related to widespread lesions involving the thoracic aorta due to Takayasu arteritis, and may be attributed to a delay in closure of the aortic second heart sound due to a decrease in aortic impedance of the diseased proximal aorta.

Using pulsed Doppler echocardiography and cineangiography, the significance of pulmonic valve ring dimensions in the genesis of pulmonic regurgitation (PR) was studied in 40 patients, including 12 with valvular disease, 19 with coronary artery disease and nine with the normal heart. In nine of the 40 subjects, pulmonary hypertension (mean pulmonary artery pressure greater than or equal to 20 mmHg) was observed. The criterion for diagnosing PR was disturbed flow patterns recorded just below the pulmonic valve which spanned more than 40% of diastole, exceeding 1.5 KHz in peak frequency (corresponding to a flow velocity of about 50 cm/sec). Sagittal and transverse diameters of the pulmonic valve ring (PRDs, PRDt) at the upper edge of the pulmonary sinus, and the sagittal diameter of the pulmonary sinus (PSD) at the level of its maximal bulging were measured using pulmonary angiography. PR was detected in 15 subjects (37.5%). The prevalence of PR among three groups regardless of the absence or presence of pulmonary hypertension was not significantly different. The peak frequency of the regurgitant flow signals as well as the farthest point of the signals detected did not differ among the three groups irrespective of pulmonary hypertension. The ratio of the PRDs to the PRDt (PRDs/PRDt) was greater in patients with PR than in those without PR (p less than 0.001), but no correlation was established between PRDs/PRDt and mean pulmonary artery pressure. The PRDt index and PRDs index (normalized by body surface area) correlated well with the mean pulmonary artery pressure (r = 0.70, p less than 0.001 and r = 0.62, p less than 0.001, respectively). PSD also correlated with the mean pulmonary artery pressure (r = 0.49, p less than 0.01), whereas, PSD/PRDs correlated inversely with the mean pulmonary artery pressure (r = 0.40, p less than 0.01), indicating a relatively more prominent dilatation of the PRDs than of the PSD in cases with pulmonary hypertension. These results suggest that the etiology of PR in our series of patients was primarily attributable to the distortion of the pulmonic valve ring. The wide-spread concept that pulmonary hypertension dilates the pulmonic valve ring, leading to the development of PR, should be criticized.