Flow-mediated vasodilation during pacing of the free epigastric artery bypass graft early and late postoperatively.

OBJECTIVES: The free epigastric artery bypass graft is proposed as an alternative conduit to the saphenous vein graft, known for its high rate of attrition. The aim of our study was to assess its endothelial function in vivo. BACKGROUND: The endothelium of arterial bypass grafts plays a role in both the performance and the patency of such grafts. METHODS: We studied 73 epigastric grafts early (mean +/- SD 10 +/- 3 days) and 36 late (12 +/- 5 months) after coronary bypass surgery with quantitative angiography at rest, after 2 min of atrial pacing (130 beats/min) and after injection of isosorbide dinitrate (1 to 2 mg) into the graft. RESULTS: At rest, mean epigastric graft diameter was lower in the late than in the early postoperative period (2.26 +/- 0.39 vs. 2.61 +/- 0.49 mm, p < 0.001). Early after operation, epigastric grafts with a small or an intermediate runoff, but not those with a large runoff, were capable of vasodilation with nitrates (+0.09 +/- 0.10 mm). Late after operation, vasodilation after administration of isosorbide dinitrate was similar in epigastric grafts with a large runoff and in those with a small or intermediate runoff (+ 0.23 +/- 0.09 vs. +0.23 +/- 0.18 mm). Significant vasodilation during pacing was observed late (+4 +/- 9%, p < 0.01) but not early postoperatively, except in a subset of patients with grafts capable of vasodilation after nitrates. A correlation between the response to nitrates and the response during pacing was observed early (r = 0.579, p < 0.001) and late postoperatively (r = 0.530, p = 0.02). CONCLUSIONS: Flow-mediated vasodilation during pacing was observed in most epigastric grafts late, but not early, after operation. This endothelium-dependent dilation was correlated with the importance of the vasodilation observed with nitrates (endothelium-independent), which was related to the importance of the runoff only in the early postoperative period. The ability of epigastric grafts late postoperatively to dynamically adapt their dimensions to an acute increase in demand could contribute to the good functional results of this new alternative arterial graft.

Functional evaluation of internal mammary artery bypass grafts in the early and late postoperative periods.

OBJECTIVES: We sought to determine whether internal mammary artery grafts adapt to an increase in myocardial flow demand and whether they restore maximal flow reserve. BACKGROUND: Although mammary grafts are now considered the graft of choice for coronary artery bypass surgery, there is still controversy about whether they can provide adequate flow at periods of peak myocardial demand. METHODS: Of 28 patients with a mammary graft anastomosed to the left anterior descending coronary artery, 15 were studied early (mean [+/- SD] 8 +/- 2 days) and 13 late (19 +/- 15 months) after operation by quantitative angiography and selective intravascular Doppler analysis at baseline, during pacing and after injection of papaverine and isosorbide dinitrate into the graft. Eleven patients with a normal left anterior descending artery served as control subjects. RESULTS: At baseline, mean graft diameter (2.39 +/- 0.41 vs. 2.42 +/- 0.45 mm) and bypass flow (38 +/- 22 vs. 30 +/- 12 ml/min) were similar in the early and late postoperative periods. Significant and similar vasodilation was observed in mammary grafts after administration of papaverine (+6 +/- 5% vs. +9 +/- 6%) and nitrates (+14 +/- 7% vs. +16 +/- 9%) both early and late after bypass surgery. Graft diameter increased during pacing late (+6 +/- 3%, p < 0.05) but not early after operation. Bypass flow increased similarly during pacing in both groups, but maximal flow reserve induced by papaverine was significantly lower in mammary grafts studied early (2.70 +/- 0.62) than those studied late (3.66 +/- 0.81, p < 0.01) and in normal coronary arteries (4.05 +/- 0.96, p < 0.001). CONCLUSIONS: An increase in myocardial blood flow induced by pacing resulted in vasodilation of mammary grafts in the late but not in the early postoperative period. Significant vasodilation of mammary grafts after papaverine and isosorbide dinitrate administration was observed both early and late after operation. However, bypass flow reserve after papaverine injection was significantly lower in the early postoperative period but normalized over time. This finding seems unrelated to the conduit; rather, it appears to be related to the periphery and could be the result of injury to the microvasculature during operation.

Shear stress-induced changes in platelet reactivity.

We have investigated the effects on platelet function of a physiologic shear stress. The aggregation to thrombin and collagen, the release reaction [(14C) serotonin] and the procoagulant activity of washed platelet suspensions were assayed on samples undergoing laminar oscillatory flow for 20 minutes at 37 degree C in polyethylene tubes, and on paired samples kept at rest. The pulse rate was established at 72 cycles per minute and the shear stress at the wall estimated at 26.2 dynes/cm2. The platelet suspensions were prepared at 37 degree C from blood samples of 15 healthy volunteers and 15 patients with the diagnosis of coronary artery disease proven by angiography. Our results show enhancement of platelet aggregation in samples undergoing oscillatory flow. Furthermore, platelets from coronary patients gained additional procoagulant activity. However, no change was encountered in the rate and speed of the release reaction. It is concluded that exposure to a high shear stress within an oscillatory flow system enhances platelet reactivity; this reaction may take part in the production of platelet and coagulation changes seen in the atherosclerotic patient and after strenuous physical exercise.

Angiographic evaluation of the natural history of normal coronary arteries and mild coronary atherosclerosis.

Between September 1966 and September 1976, a group of 48 patients with normal coronary arteries or nonsignificant coronary atherosclerosis documented in a first coronary arteriogram underwent a second angiogram because of persistent or recurrent chest pain. The interval between studies was 13 to 108 months (mean 42 months). The indication for the first angiogram was typical or atypical anginal pain. The patients were separated into two groups according to the results of the first angiogram. Group I included 22 patients, 9 men and 13 women, with normal coronary arteries (mean age 49 years, range 28 to 62). Group II included 26 patients, 18 men and 8 women, with coronary stenosis of less than 50% of intraluminal diameter (mean age 49 years, range 38 to 63). The second angiogram revealed normal coronary arteries in all 22 patients in Group I but showed progression of diseases in 7 (27%) of the 26 patients in group II. The coronary arterial narrowings were greater than 50% in four patients and greater than 70% in only two patients. The clinical course, coronary risk factors and interval between angiograms were not useful predictors of progression of disease. The data suggest that coronary artery disease is unlikely to developed in adults with normal coronary arteries and that roughly 75% of adults with nonsignificant atherosclerosis will not show progression of disease over a 3 to 4 year period.

Noninvasive prediction of pulmonary hypertension in chronic obstructive pulmonary disease by Doppler echocardiography.

Thirty-six patients with chronic obstructive pulmonary disease (COPD) were studied by pulsed Doppler echocardiography. In 32 of the 36 patients, adequate Doppler signals were obtained in the pulmonary arterial trunk and correlated with right cardiac hemodynamics. The studied group included 26 patients with mean pulmonary arterial pressure (MPAP) greater than 20 mm Hg at rest (group A, with pulmonary hypertension) and six patients with MPAP of 20 mm Hg or less (group B, without pulmonary hypertension). A control group (group C) consisted of 12 subjects with normal hemodynamic data and pulmonary function. Analysis of Doppler data included flow velocity curve pattern, presence of a negative presystolic velocity, right ventricular pre-ejection period (RVPEP) and ejection period (RVEP), time between onset and peak of pulmonary velocity (time to peak velocity, TPV) and derived ratios of TPV/RVPEP and TPV/RVEP. In patients with pulmonary hypertension, the Doppler flow velocity curve in the pulmonary trunk showed a rapid acceleration and an early deceleration. The mean value for TPV was 78 +/- 12 msec in group A, 115 +/- 11 msec in group B, and 127 +/- 10 msec in group C. In patients with COPD, significant correlations were observed between TPV and log10 MPAP (r = -0.77; SEE = 0.07) and between TPV and log10 total pulmonary resistances (r = -0.84; SEE = 0.05). Accordingly, pulsed Doppler echocardiography may be a useful tool to predict pulmonary hypertension due to chronic pulmonary disease.

Coronary artery bypass grafting with the inferior epigastric artery. Midterm clinical and angiographic results.

Between December 1988 and September 1993, 157 patients (141 men, 16 women, average age 60.2 years, range 37 to 78 years) underwent a complete myocardial revascularization with 157 inferior epigastric artery grafts and 285 internal mammary artery grafts (281 in situ, 4 free grafts). A total of 543 distal arterial anastomoses (average 3.4, range two to five per patient) were constructed, 376 with the internal mammary artery and 167 with the inferior epigastric artery. The inferior epigastric artery grafts were anastomosed to two left anterior descending, 5 diagonal, 34 circumflex, and 126 right coronary arteries. The indications for the use of the inferior epigastric artery were the unavailability of conventional conduits in 56 patients and a favorable anatomy or a young age in 101 selected patients. The clinical follow-up averages 31.8 months (range 6 to 62 months). Four patients died early, and there were three perioperative nonfatal myocardial infarctions. Eight patients required early reoperation for thoracic bleeding (2) or drainage of an abdominal parietal collection (6). There were four late deaths (2 sudden deaths, 2 noncardiac causes) and one nonfatal myocardial infarction. Angina recurred in nine patients, of whom one required reoperation and three underwent successful percutaneous balloon angioplasty of a native coronary artery (2) or an old saphenous vein graft (1). An early recatheterization was obtained before discharge (average 11 days) in 135 patients: 132 of 135 inferior epigastric artery grafts were patent. Seventy-seven patients underwent a second angiographic restudy 6 to 43 months after the operation. Forty-four of the 48 inferior epigastric artery grafts restudied within the first postoperative year (average 8.5 months) were patent, but eight showed a diffuse narrowing. Twenty-eight of the 29 inferior epigastric artery grafts examined angiographically between 13 and 43 months (average 25 months) were open, and among those 29, 25 were widely patent, perfectly matching the receiving coronary artery. Most of the occluded or narrowed inferior epigastric artery grafts were grafted onto coronary arteries with mild stenosis at restudy. Five patients underwent a third angiographic reexamination up to 60 months after the operation (average 39 months). All five inferior epigastric artery grafts were widely patent. The early attrition rate of the inferior epigastric artery, as for any free arterial graft, is probably the result of both the loss of a true pedicle and the need for constructing an additional proximal anastomosis. The fact that the patency rate of the inferior epigastric artery graft seems to remain stable beyond 1 year could suggest a good durability in the future.

Use of the inferior epigastric artery for coronary bypass.

Between December 1988 and April 1991, 74 free inferior epigastric arteries were used in 73 patients for coronary artery bypass grafts. In addition, 72 of the patients received a left internal mammary artery for single or sequential grafting to the left anterior descending system and 62 a right internal mammary artery to the circumflex or the right coronary artery. Twenty-seven patients had no saphenous vein available, and two had no suitable internal mammary artery; in an attempt to make a complete arterial revascularization, we chose the inferior epigastric artery as an alternative conduit in 24 young patients and in 10 reoperations; bilateral internal mammary artery dissection was avoided in four patients with impaired lung function and in six patients with selected two-vessel disease to spare one internal mammary artery. The technique for harvesting the inferior epigastric artery is described. Fifty-three inferior epigastric artery grafts were anastomosed to the distal right coronary artery or to its branches, 18 to the distal obtuse marginals of the circumflex artery (three as sequential grafts and one as a natural Y graft), and three to the left anterior descending system. The mean number of distal anastomoses is 3.60 per patient. Seventy proximal anastomoses of the inferior epigastric artery were made to the aorta and four to one internal mammary artery. There were four early deaths and one nonfatal myocardial infarction. Four abdominal wound hematomas needed surgical drainage. Sixty-one patients underwent angiographic study on postoperative day 10:59 of 61 inferior epigastric artery grafts (63 of 65 inferior epigastric artery distal anatomoses) and 111 of 111 internal mammary artery grafts (155 of 156 internal mammary artery distal anastomoses) were patent. Clinical follow-up of all the survivors (100% follow-up) could be obtained with a mean period of 9 months (1 to 28 months). There was no late cardiac death, no infarction, and all the patients were free of angina. Nineteen patients underwent a 6-month postoperative angiographic study. Seventeen of 19 inferior epigastric artery grafts were patent and 16 of 19 were intact; 34 of 34 internal mammary artery grafts (46 of 47 internal mammary artery distal anastomoses) were patent and intact. In conclusion, free inferior epigastric artery grafts can reach the diaphragmatic ischemic areas of the heart. The early patency rate and the clinical results are encouraging but only long-term evolution and evaluation can determine the true efficacy of the inferior epigastric artery graft as a reliable conduit for coronary artery bypass graft operations.

Revascularization of the circumflex artery with the pedicled right internal thoracic artery: clinical functional and angiographic midterm results.

Retroaortic crossing of the pedicled right internal thoracic artery for revascularization of the circumflex artery used in combination with a pedicled left internal thoracic artery anastomosed to the left anterior descending artery and its branches is an attractive technique to achieve an extensive arterial revascularization of the left ventricle. However, there is a suspicion that pulling the right internal thoracic artery through the transverse sinus could compromise its blood flow capacity and patency. Between January 1990 and July 1994 this technique was applied in 256 patients (202 men, 54 women; average age 62 years, range 31 to 80 years). Sixty-one patients had two-vessel disease and 195 had three-vessel disease. Seventeen patients were undergoing a reoperation. Twenty-two had a left ventricular ejection fraction of 40% or less. Thirty had diabetes. Twenty-eight had morbid obesity. The right internal thoracic artery was directed to the circumflex artery (259 anastomoses) through the transverse sinus and the left internal thoracic artery was anastomosed to the left anterior descending artery and its branches (375 anastomoses) in all patients. The 195 patients with three-vessel disease received additional coronary artery bypass grafts to the right coronary artery (93 saphenous vein grafts, 89 free inferior epigastric artery grafts, 12 pedicled right gastroepiploic artery grafts). In total, the 256 patients received 833 distal anastomoses (average 3.2, maximum 5 per patient) and 634 distal anastomoses were internal thoracic artery anastomoses (average 2.4, maximum 4 per patient). Three patients died early and eight had a nonfatal myocardial infarction. Seven patients needed postoperative intraaortic balloon pump support. Six patients underwent early reoperation because of excessive bleeding. Sternal dehiscence occurred in four patients. One of these four patients died of the complication 10 months after the operation. No patient was lost to follow-up (average 33 months). During follow-up, two sudden deaths and six noncardiac deaths occurred. Two patients had a nonfatal myocardial infarction and 12 had recurrence of angina. There were no late reoperations. One patient underwent a successful percutaneous balloon angioplasty of a native left anterior descending artery. Seventy-four patients, enrolled in prospective angiographic studies, underwent a postoperative recatheterization (average 13.2 months, range 6 to 58 months). Seventy-three of the 74 right internal thoracic artery grafts were patent. In comparison, 74 of 74 of the left internal thoracic artery grafts (106/107 anastomoses) were patent. Maximal stress thallium-201 scintigraphy results, obtained in 25 of those patients, did not reveal ischemia in the area of the circumflex artery.(ABSTRACT TRUNCATED AT 400 WORDS)

Aortic valve replacement with allograft/autograft: subcoronary versus intraluminal cylinder or root.

From April 1990 to May 1994, 89 patients (median age, 42 years; range, 10 days to 66 years) underwent aortic valve or root replacement with allografts or autografts. Thirteen patients were less than 18 years old at the time of operation. Indication for aortic valve replacement was aortic stenosis (50 patients, 56%), small stenotic prosthesis (2 patients, 2%), aortic valve endocarditis (19 patients, 21%), isolated aortic regurgitation (17 patients, 19%), and type II truncus arteriosus (1 patient, 1%). The subcoronary implantation was used in 45 patients (group A), and implantation of an intraluminal cylinder (16 patients) or complete root replacement (28 patients) was performed in the remaining 44 patients (group B). The Ross procedure was performed in 22 patients. Intraoperative transesophageal echocardiography was used routinely. Five patients died in the early postoperative period (6%), 2 in group A and 3 in group B. Three other patients required immediate replacement of a failing graft by a mechanical prosthesis (1 in group A and 2 in group B). There has been no late death. All survivors remained in New York Heart Association functional class I and were free of thromboembolic complications. Endocarditis occurred in 2 patients, 1 year after operation. Both were successfully treated medically. Echocardiographic studies were obtained serially in every patient. Four patients, 2 in group A and 2 in group B underwent reoperation because of mild-to-moderate aortic regurgitation (rate of reoperation, 5%). Two valves were repaired and two were replaced by an allograft.(ABSTRACT TRUNCATED AT 250 WORDS)

Operation for unstable angina pectoris: factors influencing adverse in-hospital outcome.

Coronary artery bypass grafting for the treatment of unstable angina is still associated with increased operative risk and postoperative morbidity. The impact of the extended use of arterial grafts on early results is incompletely defined. In a 7-year period (1986 to 1993), 474 patients (average age, 65 years; range, 34 to 85 years) underwent coronary artery bypass grafting for the treatment of unstable angina. Sixty-eight patients were operated on emergently and 406 urgently. They received an average of 3.0 distal anastomoses (range, 1 to 6). Seventy-nine patients had exclusively venous grafts, 316 had one internal thoracic artery graft, 79 had bilateral internal thoracic artery grafts, and 20 had inferior epigastric artery grafts. Sequential internal thoracic artery grafting was performed in 70 patients. Redo operations were performed in 26 patients. Thirty-four patients (7.2%) experienced a new myocardial infarction. Eighty-nine patients (18.8%) had an intraaortic balloon pump inserted preoperatively, intraoperatively, or postoperatively. Eight patients (1.7%) died intraoperatively and 24 patients (5.1%) died postoperatively. Seventy-seven patients (16.2%) had an adverse outcome, as shown by the need for an intraaortic balloon pump (intraoperatively or postoperatively) or hospital death, or by both. Forty variables were examined by multivariate analysis for their influence on the occurrence of an adverse outcome. Aortic cross-clamp time (p = 0.0004), transfer from the intensive care unit (p = 0.0023), female sex (p = 0.0023), operation performed in early years (p = 0.0041), left ventricular aneurysm (p = 0.0068), the number of diseased coronary vessels (p = 0.0312), and reoperation (p = 0.0318) were all found to be significant independent predictors of increased risk.(ABSTRACT TRUNCATED AT 250 WORDS)

The Ross operation: mid-term results.

BACKGROUND: The Ross operation, although more demanding, is now widely accepted as an alternative solution for aortic valve replacement in young adults and children. A review of our experience to assess the mid-term results with the Ross operation is presented. METHODS: From June 1991 through October 1997, 80 patients (mean age, 31 years) underwent aortic valve or root replacement with pulmonary autografts. Indications for operation were predominant aortic stenosis in 38 patients, aortic incompetence in 42 patients including endocarditis in 3 patients. Congenital lesions were present in 57 patients, either at pediatric (27 patients) or adult age (30 patients). Transthoracic echocardiography was performed preoperatively in all patients and serially after operation with the aims of measuring aortic and pulmonary annuli, evaluating transvalvular gradients and incompetence, and studying the left ventricular function. Intraoperative transesophageal echocardiography was used routinely. Complete root replacement was performed in 52 patients, intraluminal cylinder in 25 patients, and subcoronary implantation in 3 patients. RESULTS: One patient died in the early postoperative period (1.2%). There was no late death. The actuarial survival at 5 years was 98%+/-1%. All survivors remained in New York Heart Association functional class I and were free of complications and medications. No gradient or significant aortic incompetence could be demonstrated in 73 patients. One patient developed late aortic incompetence grade 3 and reoperation is considered. On the pulmonary outflow tract, 6 patients had gradients between 20 and 40 mm Hg as calculated on echocardiography. CONCLUSIONS: The pulmonary autograft gives excellent mid-term results with low mortality and no morbidity. It completely relieves the abnormal loading conditions of the left ventricle, resulting in a complete recovery of left ventricular function in most patients.

Doppler-derived left ventricular rate of pressure rise determination in presence of severe acute mitral regurgitation in pigs.

Doppler-derived left ventricular (LV) rate of pressure rise (Dop LV DeltaP/Deltat) is described as an index of LV performance in the presence of mitral regurgitation (MR). This study was designed to define more accurately the accuracy of the method in the presence of severe MR. Ten pigs were anesthetized and monitored. MR was gradually created. At each grade of MR, preload was manipulated with the intent of modifying LV end-diastolic area value within a range of +/-20%. Concurrently, the mean left atrial pressure (LAP) was recorded, MR was quantified by the mitral to aortic velocity-time integral ratio (mitroaortic VTI ratio), Dop LV DeltaP/Deltat was calculated, and peak LV dP/dt was derived from LV catheterism data. During the procedure Dop LV DeltaP/Deltat gradually underestimated peak LV dP/dt. This difference was correlated to the mean LAP (P < 10(-5)) and mitroaortic VTI ratio (P < 10(-5)) and became clinically significant when the mean LAP was superior to 21 mm Hg.

Noninvasive functional assessment of left internal mammary artery grafts by transcutaneous Doppler echocardiography.

A noninvasive method to assess left internal mammary artery (LIMA) patency and function would be useful because this vessel is frequently used for revascularization of the left anterior descending coronary artery. The purpose of this study was to assess the feasibility of measuring changes in LIMA velocities by transcutaneous Doppler during dipyridamole-induced vasodilation. Twenty-five patients with a LIMA graft anastomosed to the left anterior descending coronary artery were studied at least 1 month after surgery by the use of a 5 MHz transducer placed in the left supraclavicular fossa. Doppler velocity parameters were measured at baseline and after intravenous administration of dipyridamole. Dipyridamole increased mean velocity by 127% +/- 54% (p < 0.001), systolodiastolic velocity time integral by 89% +/- 31% (p < 0.001), and diastolic-to-systolic peak velocity ratio from 0.7 +/- 0.3 to 1.2 +/- 0.4 (p < 0.001). The dipyridamole-to-baseline mean velocity ratio was 2.3 +/- 0.5. We conclude that it is possible to measure dipyridamole-induced changes in LIMA flow velocities and thus obtain an index of LIMA blood velocity reserve by transcutaneous Doppler echocardiography.

Successful Cox-maze III procedure combined with mitral valve replacement in a massively thrombosed left atrium.

A case is reported of chronic atrial fibrillation resulting from long-standing rheumatic mitral stenosis complicated by a massively thrombosed left atrium. In this patient, restoration of sinus rhythm and atrial transport function was performed using a Cox-maze III procedure with mitral valve replacement.

Pneumococcal aortic valvar endocarditis with atrio-ventricular perforation.

A case of pneumococcal endocarditis, complicated by a left ventricular-right atrial fistula and a rapidly progressing cardiac failure in a 56 year-old man, is reported here. In the acute period, an aortic valve prosthesis was installed and the atrio-ventricular fistula was closed with patches of pericardium. After serious post-operative complications, the patient left the clinic, cured of his bacterial endocarditis. He unfortunately died two months later of a massive myocardial infarction caused by a previously unrecognized atheromatous stenosis of the anterior descending branch and occlusion of the circumflex vessel. The authors discuss the bacteriological, anatomopathological and clinical aspects of this rare complication of bacterial endocarditis in light of the current available literature.

Association between stroke and atrial septal aneurysm assessed by transesophageal echocardiography in a cardiologic population.

Atrial septal aneurysm (ASA) is now recognized as a source of emboli. Its prevalence in a general population remains controversial. We assessed, in a cardiologic population, the prevalence of ASA, the association with cerebrovascular events, the role of associated interatrial shunting and age. Four hundred and ninety-four consecutive patients were referred for transesophageal echocardiography with contrast. The prevalence of ASA in two groups, with (A) and without (B) cerebrovascular events were compared. In group A, we studied the prevalence of ASA according to the clinical presentation (stroke, TIA and peripheral emboli in limbs). An ASA was found in 38 patients (8%). The prevalence of ASA was higher in group A (16%) than in group B (4%) (p < 10(-5)). Prevalence of ASA was not significantly different in stroke, TIA and peripheral emboli subgroups. There was no difference in prevalence of ASA in stroke or TIA subgroups according whether age was < 55 years or > or = 55 years. Prevalence of all types of vascular events was increased when ASA was associated with an interatrial shunt. Our results support the assumption that ASA is a potential source of cerebrovascular events, whatever the clinical presentation or age. Presence of interatrial shunt increases the risk of stroke in subjects with ASA.

[Study of coronary flow in man]. / Etude du flux coronarien chez l'homme.

Especially for the last decade, measurement of total and regional coronary blood flow has raised a considerable interest. Various techniques resorting to indicators introduced into the systemic or the coronary circulation are used. Measurement of the coronary blood flow is derived from the pattern of myocardial indicator uptake or washout curves. The currently available techniques for quantitating coronary flow include inert diffusible gases, radioisotopes and continuous thermodilution; each of these has some methodological limitations. Moreover, regulation of coronary circulation depends upon several factors, and quantitative assessment of coronary perfusion in patients with ischemic heart disease has raised appreciable difficulties. Recently, however, measurement of myocardial blood flow during stress in subjects with coronary artery disease has yielded promising results. The importance of these techniques, in assessing the functional consequences of coronary stenoses, is multifold and their clinical applications will grow quickly.

Left atrial myxoma causing fluttering of the anterior mitral leaflet.

This report describes the M-mode echocardiographic features of a left atrial myxoma, before and after excision of the tumor. Preoperative M-mode echocardiogram demonstrated fine diastolic fluttering of the anterior leaflet of the mitral valve which disappeared after surgery. Preoperative aortography and minutious examination of the aortic valve during operation excluded any associated lesion of the aortic valve. The fluttering of the anterior mitral valve is probably related to turbulent blood flow around the tumor prolapsing between mitral leaflets during diastole.

Influence of moxaprindine treatment on ventricular arrhythmias occurring during maximal exercise stress testing.

Moxaprindine, a new anti-arrhythmic drug, with characteristics similar to aprindine, has been demonstrated to be highly effective in suppressing ventricular arrhythmias occurring before, during and after maximal exercise stress testing. This effect was obtained both in subjects with clinically normal hearts and in a limited number of patients with ischemic heart disease. These findings demonstrate the efficacy and safety of anti-arrhythmic treatment by drugs prolonging ventricular depolarization for ventricular arrhythmias occurring during exercise.

[Conduction disorders in aortic valve diseases]. / Troubles de conduction dans les valvulopathies aortiques

Among 304 cases of aortic valvulopathies studied for surgical selection, the authors have found a high incidence of conduction disturbances (16% in aortic stenosis and 18,4% in aortic regurgitation). The conduction defects are mostly intraventricular among stenosis isolated or associated to regurgitation and mostly atrio-ventricular among pure aortic insufficiencies. The highest incidence (30%) being found in patients with bacterial endocarditis acute or healed. The incidence of conduction disturbances increases with age, with the presence of valvular calcifications, of left ventricular strain or failure, of coronary insufficiency and angina... practically with the duration and the severity of the valvular disease. Surgical risk is heavier and natural prognosis poorer in valvulopathies with conduction disturbances. But these disturbances never contraindicates surgery : it is sometimes necessary to insert a pacemaker with or without valvular replacement mostly in aortic stenosis with infrahisian conduction defects. During hemodynamic investigation of such cases one must be ready to stimulate the heart, particularly during right heart catheterization of patients with complete left bundle branch block.