P wave changes on exercise in patients with isolated mitral stenosis

Patients with mitral stenosis usually showed a marked increase in the P negativity following exercise. The P terminal force in Lead V₁ in 20 cases with isolated mitral stenosis was ?0.090 mm. sec. before exercise, which changed to ?0.177 mm. sec. following the single Master two-step test.Normal adults never showed such changes on exercise. The phenomenon was considered to be due to the posterior rotation of the P wave vector in the horizontal plane, which was induced by the enlargement of the left atrial wall on exercise.     

Diastolic mitral annular motion in normal subjects and patients with coronary artery disease

The purpose of this study was to evaluate the characteristicsof mitral annular motion during diastole in 28 normal subjects,40 patients with prior myocardial infarction (MI), and 23 patientswith coronary artery disease but without prior MI. Mitral annularmotion during diastole was obtained from the apex by M-modeechocardiography at the posterior wall of the left ventricle.Determinants of mitral annular excursion during early (MAE-E)and late diastole (MAE-L) were investigated in all subjects.Differences in the MAE-E, MAE-L, and the MAE-L.MAE-E ratio werecompared among the three patient groups. The Doppler-derivedtransmitral flow velocity-time integral during early (El) andlate (AI) diastole and mitral annular excursions during diastolewere obtained in 55 other patients with a prior MI and in 29healthy volunteers. The relationships between the MAE-L: MAE-Eratio and AI: EI ratio in these two groups were studied. The MAE-E was determined mainly by heart rate and left ventricularejection fraction (LVEF). The MAE-L was determined only by age.The magnitude of MAE-E was significantly less in patients witha prior MI than in normal subjects (P<0.01). However, theMAE-L did not differ among the three groups. The MAE-L.MAE-Ewas higher in patients with a prior MI than in normal subjects(P<0.05), and was significantly correlated with AI: EI inhealthy volunteers (r=0.65, P<0.001) and in patients witha prior MI (r=0.50, P<0.001). The MAE-E in patients with a prior MI decreases in proportionto the deterioration in LVEF. The relative at rial contributionto left ventricular longitudinal distension is increased inpatients with a prior MI and diastolic mitral annular motionhas a significant relationship to the transmitral flow. Thesefindings suggest that mitral annular motion during late diastoleplays an important role in maintaining left ventricular fillingin patients whose left ventricular systolic function has deteriorated.     

Tight mitral stenosis with normal unilateral pulmonary capillary pressure

There are few reports of severe mitral stenosis with normal pulmonary artery wedge pressure. In order to illustrate this problem we present two adult patients with these abnormalities. Both patients had intact interatrial septum with partial anomalous pulmonary venous drainage, one to the inferior vena cava (The Scimitar Syndrome) and the other to the superior vena cava. In the first case the right pulmonary artery wedge pressure was 11 mm Hg. In the second case this pressure was only 8 mm Hg. Pulmonary arteriograms are of paramount importance in the diagnosis and surgical management. In both cases the surgical procedure with mitral commissurotomy and transplant of the anomalous pulmonary veins to the left atrium was successful.     

Myocardial enzyme activities in patients with mitral regurgitation or mitral stenosis

To determine the adaption of myocardial metabolism in mitral regurgitation and mitral stenosis, human papillary muscles obtained during open heart surgery were analysed to measure selective enzyme activities in energy metabolism. All enzyme activities were expressed per unit dry weight muscle, per unit alkali soluble protein, and per unit total creatine and the different results compared. The activities of enzymes concerned with mitochondrial energy production and energy transfer (namely, citrate synthase and mitochondrial creatine kinase) tended to be higher in papillary muscles from hearts with mitral regurgitation than in those with mitral stenosis. The activities of enzymes concerned with cytoplasmic energy production (creatine kinase MM, lactate dehydrogenase, and phosphofructokinase) did not show statistically significant differences between mitral regurgitation and mitral stenosis. The ratio of creatine kinase MB activity to total creatine content showed the greatest difference when papillary muscles from patients with mitral regurgitation and mitral stenosis were compared (31% higher in mitral regurgitation; p less than 0.001). The specific function of creatine kinase MB, which is located in cytoplasm, is not well defined. Creatine kinase MB activity increases with extreme endurance training of human skeletal muscle. Thus the higher creatine kinase MB activity in papillary muscle of mitral regurgitation may represent an adaptation to increased physical demand.     

Radiographic measurement of the right auricle in normal subjects and patients with pulmonary valvular stenosis

The assessment of the size of the right atrium in the postero-anterior X Rays projection is based in the morphology and size of the right lower cardiac border. This segment of the cardiac silhouette has not been exhaustively studied and it does not appear in atlas or textbooks in cardiology and radiology. We measured its length (L-D-D') and its convexity (A-D-D'). We obtained the measurements of normal cases and 73 patients with congenital valvular pulmonary stenosis correlated to the body surface area (BSA m2). All cases were studied with cardiac catheterization and angiocardiography. We concluded that all cases with measurement higher than normal value must be considered abnormal but other structures superimposed over the cardiac silhouette must be ruled out, such as thymus gland, intrathoracic tumors, etc..     

Intima-media thickness in patients with rheumatic mitral stenosis

The aim of the study was to determine carotid artery intima-media thickness (IMT) in patients with rheumatic mitral stenosis (RMS). Between January 2001 and December 2003, 112 consecutive patients who had been diagnosed with RMS were screened. Patients with known cerebrovascular disease, coronary artery disease, diabetes, hypertension, left ventricular hypertrophy, hyperlipidemia, abnormal laboratory results, smoking, or age over 50 years were excluded. Forty-eight patients (43 women, 5 men, mean age 39.7 +/-8.3 years) with RMS without risk factors were enrolled in the study. Age- and sex-matched healthy individuals (n = 48; 43 women, 5 men, mean age 39.6 +/-8.6 years) with normal echocardiographic findings constituted the control group. Carotid IMT was determined by using a high-resolution ultrasound system equipped with a 7-MHz imaging probe (Acuson 128 XP CI) with a computer measurement software. The mean common carotid artery IMT thicknesses both in the right (0.604 +/-0.112 mm vs 0.521 +/-0.072 mm) and in the left side (0.581 +/-0.097 mm vs 0.516 +/-0.065 mm) were significantly higher in patients with RMS than in the control group (p < 0.001). Backward stepwise logistic regression analysis identified RMS as independent predictors of increased IMT (OR, 17.25 (CI, 3.99 to 76.28), p <0.001). The present study demonstrated that RMS is associated with increased IMT. The findings indicate that in patients with RMS not only valvular but also systemic endothelium is damaged.     

P-wave dispersion in patients with rheumatic mitral stenosis

It has previously been shown that maximum P-wave duration and P-wave dispersion in 12-lead surface electrocardiogram (ECG) are significantly increased in patients prone to developing atrial fibrillation. Because patients with mitral stenosis (MS) are also susceptible to developing atrial fibrillation, the present study was carried out to determine whether maximum P-wave duration and P-wave dispersion are prolonged in MS patients during normal sinus rhythm. In addition, the correlation between these P-wave variables and the left atrial size, transmitral valve gradient and mitral valve area were determined. Fifty consecutive patients (40 women and 10 men; mean age 35.76±6.59 years) with MS who were in normal sinus rhythm, and a control group of 50 age- and sex-matched healthy persons were studied.A 12-lead ECG was obtained for each subject. All ECGs were scanned through a Cannon scanner at 300 dpi and saved as images in a personal computer. The minimum and maximum P-wave durations, as well as P-wave dispersion, were subsequently calculated. In addition, all patients were evaluated by echocardiography to measure the left atrial size, transmitral valve gradient and mitral valve area by planimetry. The P-wave parameters were compared between the two groups and the correlation between these parameters and the echocardiographic variables were determined in patients with MS. The most important findings included a significant prolongation of maximum P-wave duration in patients with MS compared with controls (P<0.001), and a strong correlation between the maximum P-wave duration and left atrial size (r=0.505, P<0.001), transmitral valve gradient (r=0.371, P=0.01) and a significant negative correlation with mitral valve area (r=-0.379, P=0.007). There was no correlation between the P-wave dispersion and echocardiographic parameters.