Assessment of chronic tricuspid regurgitation by colour Doppler echocardiography: a comparison with angiography in the catheterization room.

Colour Doppler echocardiographic (CDE) assessment of tricuspid regurgitation (TR) has been limited by the lack of an accepted model against which it can be compared. Angiography is said to be inadequate because catheter placement across the tricuspid valve could induce artifactual TR. Thirty-five consecutive patients with left-sided valvulopathy and recent heart failure were studied. Angiography was validated by CDE, which demonstrated that catheter placement across the tricuspid valve did not increase the size of the regurgitant jet in the first 30 cases. All the patients were studied with CDE immediately before performing the angiography in order to compare the findings of both techniques. From all the CDE parameters measured among the angiographic groups, the jet area overlapped the least (P = 0.024). The diameters of the right cardiac chambers were larger in angiographically severe cases (P = < 0.003 to 0.041), and a scale of severity that combined jet area and right atrium area showed an excellent correlation with angiography (r = 0.924; P < 0.001). Furthermore, maximal instant systolic gradients between the right cavities, estimated by catheterization, were lower in severe cases (P = 0.038). Assessment of these gradients by continuous Doppler can enhance recognition of severe TR. The analysis of jet area, right atrium area and regurgitant gradient by CDE can provide excellent assessment of TR.

[The potential usefulness of MIBI-99mTc SPECT at rest in identifying viable myocardium after a myocardial infarct]. / Utilidad potencial del SPECT con MIBI-99mTc en reposo en la identificación de miocardio viable tras un infarto de miocardio.

We present a 65 years-old female with a silent anterior myocardial infarction. A coronary angiogram showed a left ventricle with akinesia of segments anterior, lateral and apex. Left anterior descending artery showed a unique 95% lesion. The patient was discharged with medical treatment. Two months later the patient was readmitted with atypical angina. She was submitted to tomographic study (SPECT), with 99mTc-hexakis-2-methoxy-isobutyl-isonitrile (MIBI-99mTc) at rest. The images showed a wide area of hypocaptation in the territory of the left anterior descending artery but with differences among the different segments. This image was interpreted as suggestive of necrotic and viable myocardium. A second coronary angiogram yielded the same findings as in the first study. It was performed a successful PTCA on the left anterior descending artery lesion. A new SPECT study was performed 9 days later that showed a significant improvement of perfusion in some of the myocardial segments and a significant decrease of the internal left ventricular diameter. Isotopic left ventricular ejection fraction showed an increase from 25 to 35%. The present case suggests that the study with SPECT and MIBI-99mTc at rest may be potentially useful in the identification of viable myocardium after a myocardial infarction and assesses the importance of revascularization of the culprit artery with severe residual narrowing.

Diagnostic value of two-dimensional echocardiography in cardiac hydatid disease.

Echinococcal infection of the heart is rare. The preoperative findings, with special attention to two-dimensional echocardiography (2DE), of six patients with cardiac echinococcosis and their surgical and pathological correlations are reported. Cardiac hydatid cysts (HCs) were located in the cardiac apex in three patients, in the upper part of the interventricular septum extending towards the anterior aspect of the heart in one and in the postero-superior right atrial wall in another patient. The remaining patient had multiple intrapericardial cysts. In three patients the cysts presented as well defined, rounded, echolucent masses within the myocardial wall bulging into the cardiac chambers. In two patients, the cysts had ruptured into a cardiac chamber with loss of the characteristic 'cystic' appearance; these cysts presented as an echogenic or solid mass protruding into a cardiac chamber. Finally, another patient had one HC with echolucent appearance and another HC in a different location with echogenic appearance; this last cyst corresponded to a degenerated HC. In two cases the cyst showed a loculated internal aspect. In one patient the myocardial segment involved by the cyst had a dyskinetic movement. In all six patients, 2DE accurately demonstrated the location and morphological details of the cardiac cysts, permitted recognition of the ruptured and/or degenerated cysts and was superior to thoracic computed tomography and angiography in the preoperative assessment of these patients. Nuclear magnetic resonance imaging (one patient) gave no further information to that obtained by 2DE. We conclude that 2DE is the technique of choice for an early diagnosis of this rare entity.

Right ventricular dilated cardiomyopathy associated with primary biliary cirrhosis.

A case of right ventricular dilated cardiomyopathy associated with primary biliary cirrhosis is described. The patient was a middle aged woman, who initially complained of fatigue and itching. The diagnosis of primary biliary cirrhosis was made based on clinical, biochemical and histological evidence of the disease. Seven years later severe right-sided heart failure developed. The diagnosis of right ventricular dilated cardiomyopathy was made based on echocardiographic and angiographic evidence of a globally dilated and poorly contracting right ventricle. Left ventricular function was within normal limits. Autoimmune serology screening at this time revealed the presence of organ-specific cardiac antibody (titre 1/20) and of antinuclear antibody (titre 1/80) by indirect immunofluorescence. There were no findings of mitochondrial antibody or other non-organ specific or organ-specific antibodies. Overall, this assessment demonstrates autoimmunity in both hepatic and heart muscle disease in a patient with primary biliary cirrhosis and right ventricular dilated cardiomyopathy.

Echocardiographically revealed collapse of the right ventricle and prolonged inversion of both atria without clinical cardiac tamponade.

In a patient with a large pericardial effusion without any clinical signs of cardiac tamponade, echocardiography revealed collapse of the right ventricle and prolonged (greater than 34%) inversion of the free wall of both atria, maximal in early systole. The presence of such findings in the absence of clinical signs of haemodynamic compromise is discussed.

Arrhythmogenic effects of antiarrhythmic drugs in patients with an old myocardial infarction and asymptomatic ventricular ectopic activity as studied by programmed electrical stimulation.

In 22 patients with a previous myocardial infarction and documented Lown class II to IV asymptomatic ventricular arrhythmias, the arrhythmogenic effect of mexiletine (18 patients) and propafenone (10 patients) has been assessed by programmed electrical stimulation. Ventricular arrhythmias induced during the basal study were: repetitive ventricular responses (RVR) (11/22, 50%), nonsustained ventricular tachycardia (VT) (3/22, 14%), sustained VT (7/22, 32%) and ventricular fibrillation (VF) (1/22, 4%). The induction of sustained VT or VF increased to 50% after mexiletine and to 80% following propafenone. An arrhythmogenic effect was found in 7/11 patients (64%) without VT at the control study (P = 0.004). One patient of this group spontaneously developed sustained VT both after mexiletine and propafenone. Only 1/8 patients (13%) with sustained VT/VF at the basal study had RVR after drug administration. The R-R interval of sustained VT at the basal state tended to be faster than that after the drugs (260 +/- 60 ms vs 293 +/- 56 and 332 +/- 77 ms for mexiletine and propafenone, respectively) (P = 0.052). Statistical significance was only reached in the propafenone group (P = 0.03). Facilitation of VT induction after antiarrhythmic drugs is most likely due to a modest lengthening of refractoriness in contrast with a more evident reduction in conduction velocity within the reentry pathway. Our study illustrates that treating asymptomatic ventricular ectopic activity in patients with an old myocardial infarction may be dangerous and that antiarrhythmic drugs show a significant arrhythmogenic potential at least in the laboratory setting.

Relation of midwall circumferential systolic stress to equatorial midwall fibre shortening in chronic aortic regurgitation. Value as a predictor of postoperative outcome.

Nineteen patients with chronic aortic regurgitation and a large increase in heart size were studied before aortic valve replacement. By relating midwall circumferential systolic stress to midwall circumferential fibre shortening (Cs/Cd) before operation the patients could be divided into two well defined groups. Twelve patients (group 1) had a pronounced decrease in heart size as measured by the cardiothoracic ratio and an excellent clinical outcome six months after operation. Seven patients (group 2) had no significant decrease in heart size and a less good clinical outcome. The ratio of midwall circumferential systolic stress to end systolic volume index was significantly higher in group 1 than in group 2. Group 2 had more severe left ventricular hypertrophy determined by the ratio of the wall thickness to the minor internal radius of the left ventricle (h:r ratio), total left ventricular mass, and left ventricular mass to end diastolic volume ratio. There were no significant differences in any other haemodynamic or angiographic indices between the two groups. Thus the relation of midwall circumferential systolic stress to fibre shortening is useful in determining the prognosis in individual patients with chronic aortic regurgitation undergoing aortic valve replacement.

Early in vivo hemodynamic evaluation of the mitral Medtronic-Hall cardiac valve.

We studied the hemodynamics of 14 patients with a Medtronic-Hall prosthesis in mitral position 6 months after valve implantation. The usual hemodynamic parameters showed a striking improvement after surgery. The mean pulmonary arterial pressure decreased from (mean +/- SD) 37 +/- 10.7 mmHg to 20 +/- 6.5 mmHg (p less than 0.005). Mean pulmonary capillary pressure decreased from 24 +/- 7.1 mmHg to 10 +/- 3.0 mmHg (p less than 0.001). Cardiac output increased slightly from 3.7 +/- 0.8 L/min to 4.2 +/- 0.45 L/min, the difference not being significant. Valvular area at rest was 1.82 +/- 0.25 cm2 and increased significantly during exercise to 2.47 +/- 0.45 cm2 (p less than 0.001). The opening angle of the disk occluder reached a mean value of 64 +/- 4.6 degrees, that is 91% of the maximal theoretical opening angle. We fitted a hydraulic function gradient = Ax (Flow)n (mean r = 0.9176), to the paired data of gradient and flow obtained during progressive exercise. This procedure permitted us to establish the actual hemodynamic behavior of the prostheses which did not concur with the behavior predicted by the Gorlin formula. We conclude that the Medtronic-Hall mitral prosthesis is an acceptable alternative when mitral valve replacement is considered.

Treadmill stress testing in the evaluation of patients with valvular heart disease. Possible role in the assessment of functional capacity and severity of the lesion.

A series of 123 patients with valvular heart disease underwent treadmill stress testing (Bruce's protocol). Neither mortality nor serious complications were observed. The incidence of exercise-induced ventricular ectopy was 35% and that of complex ventricular ectopy 19%. Patients with pure left ventricular volume overload had a significantly higher incidence of exercise-induced ventricular ectopy than did patients with other valvular diseases. A significant relation was found between functional class (NYHA) and either duration of exertion or functional aerobic impairment. The NYHA classification was found to coincide in 62% of the instances with another based on the results obtained from stress testing. In patients with mitral stenosis a significant although slight correlation was found to exist between mitral valve area and duration of exercise. The inability to reach stage III of Bruce's protocol was associated with a critical mitral stenosis. A hypotensive response to exercise was frequent both in mitral stenosis and aortic stenosis. But whereas in aortic stenosis it was characteristic of the most severe lesions, in mitral stenosis it bore no relation whatsoever to severity. Thus, treadmill stress testing in valvular heart disease is safe, can be helpful in quantifying functional disability and may provide a clue as to the severity of the lesion in specific subsets.