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D Rittoo

Publications and source records attributed to D Rittoo.

32 records · Page 2Linked to original sources
PubMed1993

Intra-operative myocardial ischaemia detected by biplane transoesophageal echocardiography during transurethral prostatectomy.

Recent studies have shown an increased late mortality rate due to cardiovascular causes after transurethral compared with open prostatectomy. This has been linked to the demonstration of haemodynamic changes during transurethral prostatectomy, which may cause ischaemic myocardial injury. We used transoesophageal echocardiography (currently the most sensitive modality for detecting myocardial ischaemia) to study 26 patients during prostatectomy under general anaesthesia. Evidence of myocardial ischaemia (as shown by the development of new regional wall motion abnormalities of the left ventricle) occurred in 4 of 22 patients during transurethral and in 3 of 4 patients during retropubic prostatectomy. An intra-operative fall in systolic as well as diastolic blood pressure occurred in 21 of 22 patients during the transurethral procedure and in all 4 patients during retropubic prostatectomy. The duration of anaesthesia and the operation, and the intra-operative blood loss did not differ significantly between patients with and without evidence of intra-operative myocardial ischaemia. However, the maximum intra-operative fall in systolic and diastolic blood pressure, as well as the mass of the prostatic tissue removed, were significantly greater in patients with than in those without evidence of intra-operative myocardial ischaemia, suggesting that the latter may be related to the extent of surgery and the degree of intraoperative hypotension. In this study, 7 of 26 patients (27%) showed evidence of myocardial ischaemia during prostatectomy. However, it remains difficult to explain why intra-operative myocardial ischaemia should result in an increased cardiovascular mortality rate several years after the operation.

Aged↗
PubMed1993

Acute pulmonary artery thromboembolism treated with thrombolysis: diagnostic and monitoring uses of transoesophageal echocardiography.

The central pulmonary arteries and any thrombus within them can be imaged by transoesophageal echocardiography. Its use is reported in the diagnosis and subsequent management of a patient with acute pulmonary embolism, whose response to thrombolytic treatment was monitored by further transoesophageal studies. Transoesophageal echocardiography may be a valuable primary diagnostic procedure in patients who seem to have sustained a significant pulmonary embolus and require urgent intervention.

Echocardiography↗
PubMed1993

Additional value of biplane transoesophageal imaging in assessment of mitral valve prostheses.

OBJECTIVES: To determine whether biplane transoesophageal imaging offers advantages in the evaluation of mitral prostheses when compared with standard single transverse plane imaging or the precordial approach in suspected prosthetic dysfunction. DESIGN: Prospective mitral valve prosthesis in situ using precordial and biplane transoesophageal ultrasonography. SETTING: Tertiary cardiac referral centre. SUBJECTS: 67 consecutive patients with suspected dysfunction of a mitral valve prosthesis (16 had bioprostheses and 51 mechanical prostheses) who underwent precordial, transverse plane, and biplane transoesophageal echocardiography. Correlative invasive confirmation from surgery or angiography, or both, was available in 44 patients. MAIN OUTCOME MEASURES: Number, type, and site of leak according to the three means of scanning. RESULTS: Transverse plane transoesophageal imaging alone identified all 31 medial/lateral paravalvar leaks but only 24/30 of the anterior/posterior leaks. Combining the information from both imaging planes confirmed that biplane scanning identified all paravalvar leaks. Five of the six patients with prosthetic valve endocarditis, all three with valvar thrombus or obstruction, and all three with mitral annulus rupture were diagnosed from transverse plane imaging alone. Longitudinal plane imaging alone enabled diagnosis of the remaining case of prosthetic endocarditis and a further case of subvalvar pannus formation. CONCLUSIONS: Transverse plane transoesophageal imaging was superior to the longitudinal imaging in identifying medial and lateral lesions around the sewing ring of a mitral valve prosthesis. Longitudinal plane imaging was superior in identifying anterior and posterior lesions. Biplane imaging is therefore an important development in the study of mitral prosthesis function.

Adult↗
PubMed1993

Quantification of left-to-right atrial shunting and defect size after balloon mitral commissurotomy using biplane transesophageal echocardiography, color flow Doppler mapping, and the principle of proximal flow convergence.

BACKGROUND: The flow convergence region (FCR), a zone of progressive laminar velocity acceleration, can be imaged by color Doppler proximal to stenotic and regurgitant orifices. Theoretically, FCR proximal to a discrete circular and planar orifice consists of concentric hemispheric shells of equal and accelerating velocities centered at the orifice. According to the continuity principle, flow rate across any of these isovelocity surfaces equals flow rate through the orifice. The aim of this study was to investigate whether these principles could be applied to quantify left-to-right shunting and the size of atrial septal defects after balloon mitral commissurotomy. METHODS AND RESULTS: Biplane transesophageal echocardiography (TEE) with color flow imaging was performed on 36 consecutive patients (mean age, 57 +/- 16 years; range, 14-78 years) immediately before and within 24 hours of balloon (Inoue, n = 33; Mansfield, n = 3) mitral commissurotomy. Left-to-right atrial shunting was detected by TEE in 33 patients (92%) and by oximetry in 11 patients (31%). The radius r of FCR was measured from the first aliasing limit, at a Nyquist velocity reduced to 11 cm/sec by zero-shifting, to the orifice in the atrial septum. FCR was assumed to be hemispherical. Hence, flow rate (Q) was calculated as 2 pi r2 Vr, where Vr is the velocity at a radial distance r. The velocity profile of transatrial flow was assessed by means of high pulse repetition frequency, from which the maximum flow velocity (Vp) and the velocity-time integral (VTI) were obtained. The flow area of the atrial septal defect was calculated as Qm, the maximal flow rate, divided by Vp. Hence, shunt flow was calculated as flow area x VTI x heart rate. FCR was analyzed in two orthogonal planes. Mean Qm (38.1 +/- 26.5 versus 5.3 +/- 2.7 mL/sec), flow area (22.1 +/- 11.2 versus 4.4 +/- 2.0 mm2), and shunt flow (1,590 +/- 1,070 versus 200 +/- 130 mL/min) on transverse plane imaging were all significantly higher in patients with shunts detected by oximetry than in those without. Similar results were obtained from longitudinal plane imaging. Qm correlated well with oximetric shunt flow (r = 0.89-0.94, p < 0.001) and shunt ratio (r = 0.91-0.94, p < 0.001). Flow area correlated closely (r = 0.93-0.94, p < 0.001) with area determined by direct measurement from two-dimensional echocardiography. Shunt flow determined by FCR also correlated closely (r = 0.94-0.98, p < 0.001) with that determined by oximetry and that derived from two-dimensional echocardiography and pulsed Doppler (r = 0.96, p < 0.001). CONCLUSIONS: The flow convergence region imaged by TEE color flow mapping provides new and accurate quantitative information on atrial shunt flow and defect size after balloon mitral valvotomy. It is a quick, reliable, and fairly simple method that can be readily incorporated into routine clinical practice.

Adolescent↗
PubMed1992

Misuse of ecstasy.

Explore the source record for details and available documents.

3,4-Methylenedioxyamphetamine↗
PubMed1990

Echocardiographic and Doppler evaluation of left ventricular hypertrophy and diastolic function in black and white hypertensive patients.

Echocardiography including Doppler examination has been used to assess left ventricular hypertrophy and diastolic function in 24 patients: 12 black Negro patients and 12 white patients who were matched with respect to age, heart rate and systolic and diastolic blood pressure. Significant left ventricular hypertrophy was present with normal systolic function but impaired diastolic function with a decrease in peak E velocity, an increase in peak A velocity and reversal of the E/A ratio. In the combined groups LV mass and LVPW correlated with systolic blood pressure (P less than 0.05). In the blacks systolic and diastolic blood pressure correlated with LV mass and LVPW thickness (P less than 0.05). Septal thickness correlated only with systolic blood pressure (P less than 0.01). In contrast the indices of diastolic function did not correlate with blood pressure or with left ventricular hypertrophy. No morphological differences in the left ventricle have been shown between the two groups but both had significant left ventricular hypertrophy. Whilst diastolic function is abnormal, this appeared to be independent of either blood pressure or degree of left ventricular hypertrophy. A neurohumeral mechanism has not been discounted.

Adult↗
PubMedDate not supplied

A prospective study of left atrial spontaneous echo contrast and thrombus in 100 consecutive patients referred for balloon dilation of the mitral valve.

The aim of this study was to determine the clinical, echocardiographic, and hemodynamic predictors of left atrial spontaneous echo contrast (SEC) and thrombus, respectively, in patients referred for balloon dilation of the mitral valve and to establish the relationship between the two phenomena in this group of patients. One hundred consecutive patients (mean age 57 +/- 14 years) referred for mitral balloon (Inoue) dilation were studied prospectively with transthoracic and transesophageal (83 biplane and 17 single plane) echocardiography (TEE) combined with spectral and color Doppler modalities, immediately before the procedure. TEE was repeated within 24 hours of valvotomy in the first 55 patients. All patients also underwent comprehensive left- and right-sided heart catheterization. TEE was performed successfully in 96 patients. SEC was detected in all 65 patients in atrial fibrillation and in 14 (45%) of 31 patients in sinus rhythm. Patients with SEC were significantly older (61 +/- 13 vs 45 +/- 12 years; p < 0.001) and had larger left atrial volume (98 +/- 48 vs 64 +/- 24 ml; p < 0.001), higher mitral valve echocardiographic scores (7.4 +/- 3.2 vs 5.3 +/- 2.6; p = 0.016), lower cardiac output (3.5 +/- 1.1 versus 4.6 +/- 0.9 L/min; p < 0.001), lower peak systolic pulmonary vein flow velocity (SVm) (24 +/- 12 versus 45 +/- 11 cm/sec; p < 0.001), and correspondingly lower systolic velocity-time integral (4.0 +/- 2.6 vs 7.9 +/- 2.9 cm; p < 0.001) than had patients without SEC. There were no significant associations between SEC and either mitral valve area or anticoagulant therapy. SVm and atrial fibrillation were found to be independent predictors of SEC. In patients in sinus rhythm, SVm was the only independent predictor of SEC. After mitral balloon dilation, SEC disappeared in only two of 35 patients in atrial fibrillation and in five of eight patients in sinus rhythm. Significant mitral regurgitation occurred in the two patients in atrial fibrillation. TEE detected left atrial thrombus in 14 patients. Thrombus was significantly associated with age, mitral valve area, and the severity of SEC. The latter was found to be an independent predictor of thrombus. Two patients in sinus rhythm had evidence of left atrial mechanical dysfunction. Both patients had left atrial SEC and one had thrombus in the appendage. It is concluded that SEC in patients with severe mitral stenosis is dependent on left atrial systolic function and peak systolic pulmonary vein velocity. It is not related to mitral valve area or anticoagulant therapy.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMedDate not supplied

Posterior left ventricular pseudoaneurysm after aortic valve replacement in a patient with rheumatoid arthritis: diagnosis by transesophageal echocardiography.

A 58-year-old man with seropositive rheumatoid arthritis underwent successful aortic valve replacement because of severe aortic regurgitation. One year later, prosthetic valve endocarditis was suspected clinically and he was referred for echocardiography. On transthoracic echocardiography an unusual echo-free space adjacent to the inferobasal segments of the left ventricle and extending behind the left atrium was visible. No further diagnostic information could be obtained from precordial examinations. Biplane transesophageal echocardiography demonstrated the presence of a pulsatile pseudoaneurysm of the left ventricle arising posteriorly, close to the anulus of the mitral valve. There was no evidence of endocarditis.

Aortic Valve↗
PubMedDate not supplied

Transseptal mitral balloon valvotomy in patients with atrial septal aneurysms.

Transthoracic and transoesophageal echocardiography (TTE, TEE) were performed in 130 consecutive patients referred for mitral balloon valvotomy. Atrial septal aneurysms were diagnosed by TTE and TEE in 2 and 3 patients, respectively. All 3 patients underwent mitral balloon valvotomy via the transseptal route. The foramen ovale was found to be patent in 2 of these patients, thus rendering puncture of the interatrial septum unnecessary. In the 3rd patient transseptal catheterisation was performed through the wall of the aneurysm itself. There were no significant complications in any of these patients. No left-to-right interatrial shunting could be demonstrated by oximetry in any of the 3 patients. Transoesophageal colour flow imaging showed trivial shunting in 2 patients and none in the 3rd. Transseptal mitral balloon valvotomy can be performed safely in patients with atrial septal aneurysms, especially in those with co-existent patent foramen ovale.

Adult↗
PubMedDate not supplied

Mitral balloon valvotomy.

Until recently, surgery was the only effective treatment for patients with severe mitral stenosis. Mitral balloon valvotomy is a percutaneous technique which can achieve results comparable to surgery in selected patients.

Cardiac Catheterization↗