Mitral insufficiency secondary to coronary heart disease.

Twenty-four patients were operated on for mitral regurgitation secondary to coronary heart disease. Their common features consisted of a history of myocardial infarction, congestive heart failure, coronary occlusive disease, left ventricular dysfunction, low cardiac output, pulmonary hypertension, and increased left ventricular end-diastolic pressure. Fourteen patients were in intractable congestive heart failure at the time of operation. The operative procedures employed consisted of aneurysmectomy in 4 patients; mitral valve replacement (MVR) in 7;MVR and revascularization in 4; MVR and aneurysmectomy in 5;MVR, revascularization, and partial ventricular resection in 3; and MVR with closure of ventricular septal perforation in 1 patient. Six patients died, a hospital mortality of 25%, and only 42% had good results. The degree of associated coronary artery disease and the status of the left ventricular myocardium were the most important prognostic factors.     

Elective operations for post-infarction left ventricular aneurysms.

During a two-year period (February 1973 to February 1975) 20 consecutive patients with post-infarction left ventricular aneurysm, seen at the Wessex Cardiac and Thoracic Centre, underwent aneurysmectomy with or without aorta-to-coronary artery saphenous vein bypass grafts, ventricular septal defect closure, or valve replacement. The diagnoses were established by clinical means, plain chest radiographs, left ventriculography, and selective coronary arteriography. The indications for surgery were uncontrollable congestive heart failure and angina, ventricular arrhythmias, or a rapidly growing aneurysm. Low cardiac indices or high left ventricular end-diastolic pressure were not considered to be contraindications to operation. Resection of the left ventricular aneurysm was performed with the use of normothermic cardiopulmonary bypass with haemodilution. In addition to the aneurysmectomy, four of these patients had concomitant closure of post-infarction ventricular septal defects; four had valve replacements; two had grafts to coronary arteries; and one had both replacement of the mitral valve and a right coronary vein graft. There were two hospital deaths (10%) and two late deaths (10%), making an overall mortality of 20%. All but one of the deaths were related to coronary artery disease. The survivors are active, and their rehabilitation was satisfactory. The longest survivor is doing well two years after left ventricular aneurysmectomy, ventricular defect closure, and tricuspid valve replacement. It is evident from our experience and from the reports of others that surgery has an established place in the management of post-infarction left ventricular aneurysm.     

Acute Postoperative Digitalization of Patients with Arteriosclerotic Heart Disease after Major Surgery

Twenty patients with impaired left ventricular function during exercise, who underwent major vascular surgery for arteriosclerotic disease, were randomly digitalized in the immediate postoperative period. All patients had a smooth postoperative course. Haemodynamic measurements showed improved left ventricular function in those who received digitalis, since 60 min after full digitalization the digitalized patients had a highly significant decrease in pulmonary capillary wedge pressure (PCWP) with unchanged stroke volume index (SVI) and left ventricular stroke work index (LVSWI). The same improvement in cardiac function was present the next morning. The present study provides haemodynamic data in support of clinical studies showing a beneficial effect of prophylactic digitalization in surgical patients with clinical signs of arteriosclerotic heart disease, though not in overt failure.     

Noninvasive assessment of hemodynamic effects of mitral valve commissurotomy during rest and exercise in patients with mitral stenosis.

Noninvasive radionuclide angiocardiography (RNA) provides simple and accurate assessment of parameters of cardiac function during rest and during maximal exercise. Left ventricular function was assessed by RNA in nine patients with isolated mitral stenosis before and approximately 6 months after mitral commissurotomy. Before operation, the mean mitral valve gradient was 14.0 +/- 2.8 mm Hg, and the mean mitral valve area was 1.20 +/- 0.3 cm2. Each patient was evaluated at rest and during maximal exercise on an isokinetic bicycle ergometer before and after commissurotomy. Heart rate, ejection fraction, end-diastolic volume, stroke volume, pulmonary transit time, cardiac output, and diastolic ventricular filling rate were determined by the radionuclide technique. Before operation, patients with mitral stenosis had characteristic changes from rest to exercise which supported restriction to diastolic ventricular filling as the primary limitation in generating a cardiac output during exercise. The stroke volume was unchanged from rest to exercise. Thus the cardiac output during exercise was heart rate dependent. However, after commissurotomy the stroke volume increased from rest to exercise. Therefore, cardiac output during exercise was achieved by heart rate and an augmented stroke volume. Moreover, the pulmonary transit time was reduced during rest and exercise after operation. The maximum ventricular ejection and filling rates were markedly increased during rest and exercise after commissurotomy. These differences in hemodynamic parameters at rest and during exercise document the mechanics of increased exercise tolerance in patients with mitral stenosis after mitral commissurotomy.     

Heart valve surgery

As the general population ages the incidence of degenerative valve disease is increasing. This is reflected by the changing workload of cardiac surgeons, indicated by the rising number of heart valve operations. Improved imaging techniques facilitate diagnosis, surveillance and guide surgical management in correcting the underlying defect. Patients with valvular heart disease require close follow-up and monitoring for changes in symptomatology, valve and ventricular function. Medical therapy is limited to antibiotic prophylaxis against endocarditis. Surgery is the mainstay of treatment for symptomatic and severe lesions, and is associated with excellent haemodynamic improvements and long-term outcomes. The timing of valve surgery is critical in order to avoid irreversible consequences of ventricular dysfunction or pulmonary hypertension.     

Aortic Valve Replacement Using Local Myocardial Hypothermia

This material comprises 100 cases of aortic valve replacement. Ninety-one of the valves were replaced with the Björk—Shiley tilting disc valve prosthesis and 9 with the Smeloff—Cutter ball valve. No coronary perfusion was used during surgery. The myocardium was protected by local myocardial hypothermia, achieved by an intracoronary infusion of Bretschneider's solution (+4°C) prior to surgery. A weak and flaccid heart without coronary perfusion cannulas facilitated the surgical procedure. Myocardial function was very good and the course of the patients excellent postoperatively. Seven percent of the patients were lost within one month after operation and late mortality was 13%. A comparison between clinical and haemodynamic findings obtained 2–3 months before and one year after surgery was made in 55 patients. A marked subjective improvement was seen in all but five patients. There was a significant increase of average physical working capacity and regression of ECG-signs of left ventricular hypertrophy and strain as well as of roentgenological heart size. Angina pectoris was present in only three patients postoperatively as compared with 23 before surgery. The improvement of physical working capacity was paralleled by a significant increase of cardiac output during exercise, caused by a rise of stroke volume, heart rate on maximal load tolerated remaining unchanged. Blood pressure reactions during work were normalized in patients with both pre-operative aortic stenosis and aortic insufficiency. A significant postoperative paravalvular leakage was rare in the present material.     

Dipyridamole-thallium myocardial scanning in the pre-operative assessment of patients undergoing abdominal aortic aneurysmectomy

Dipyridamole thallium scanning (DTS) is an imaging technique with good sensitivity for coronary artery disease (CAD). The purpose of this study was to compare the haemodynamic courses and the correlation between pulmonary capillary wedge pressure (PCWP) and central venous pressure (CVP) in patients with normal DTS (Group 1: n = 12) with those whose scans demonstrated CAD (Group2: n = 11). Haemodynamic profiles were obtained prior to anaesthesia and at several times during surgery. The haemodynamic courses in both groups were similar with significant decreases in cardiac index, stroke index, and left ventricular stroke work index during aortic cross-clamping compared with values prior to anaesthesia. There were no significant changes in PCWP and CVP throughout the study. The correlations between PCWP and CVP were significant in both groups as were the correlations between the changes in PCWP and the changes in CVP observed at the time of cross-clamping. These correlations all had large standard errors of the estimate, however, making it impossible to predict the PCWP from the CVP with precision. It is concluded that, in a limited study population, an abnormal DTS did not identify patients in whom the PCWP and CVP correlated poorly during abdominal aortic aneurysmectomy.     

Encircling endocardial ventriculotomy for malignant ventricular arrhythmias. Effect on cardiac performance

Cardiac performance and hemodynamics were studied with radionuclide ventriculography in 19 survivors of aneurysmectomy and encircling endocardial ventriculotomy for recurrent, sustained ventricular arrhythmia (group I). To characterize the effect of the ventriculotomy on cardiac function, comparisons were made with a similar group of patients who underwent aneurysm surgery for angina pectoris and/or congestive heart failure (group II). Functional classification revealed no difference between the groups and they achieved the same level of exercise after surgery. No intergroup difference was found postoperatively with respect to right or left ventricular ejection fraction, regional ejection fractions, peak ejection rate, cardiac index or stroke volume. Peak filling rate was also similar, as were cardiac volumes. Exercise did not change any parameter of this intergroup similarity. The authors conclude that most patients with moderately impaired left ventricular function who undergo left ventricular aneurysmectomy with encircling endocardial ventriculotomy do not differ in postoperative hemodynamics and systolic or diastolic function from those treated with simple aneurysmectomy.     

Haemodynamic evidence for per-operative cardiac stress during transurethral prostatectomy. Preliminary communication.

Haemodynamic changes were measured during routine transurethral prostatectomy (TURP). The heart rate and stroke volume fell progressively over the first 30 min of surgery, resulting in a steady reduction in cardiac output. There was a significant increase in left ventricular afterload from commencement of the procedure. These findings demonstrate that haemodynamic responses, which are not detectable using conventional methods of monitoring, occur during TURP. Increased left ventricular afterload indicates increased myocardial work and oxygen demand which could result in myocardial ischaemia. This may contribute to the increased cardiovascular morbidity and mortality which have been reported to occur after TURP. The possible underlying mechanisms are discussed.     

Surgical management of abdominal aortic aneurysms: factors influencing mortality and morbidity--a 20-year experience.

Abdominal aortic aneurysmectomy is being performed with progressively lower operative mortality and morbidity. Three hundred thirty seven patients have had elective aneurysm repair since 1954. Factors affecting mortality and morbidity in the last 108 cases are analyzed. Seventy-four per cent of patients had pre-existing disease, either cardiac, pulmonary, renal, cerebrovascular, diabetes mellitus, or hypertension. Six patients died following operation, a mortality rate of 5.5%. One died of pulmonary and 5 of cardiac causes. No patient died of renal failure or required dialysis. A signficant feature of management is the regimen of fluid therapy using dextrose in lactated Ringer's solution during and after operation to minimize hypotensive and renal complications. No patient developed a wound infection, graft infection, wound dehiscence, stroke, or intestinal ischemia. Serious postoperative complications were largely cardiac or pulmonary. Despite recent liberalization of indications for operation, comparative figures show continued reduction in operative mortality from 17% during 1954-1961, or 7.4% during 1962-1967, to 5.5% in the 1968-1974 era. This declining mortality is related to earlier diagnosis using non-invasive methods (sonogram), simplified operative techniques, improvement in fluid management, innovations in cardiopulmonary therapy, and recognition and proper handling of unusual manifestations of aortic aneurysms.     

Transtricuspid approach in redo surgery for post-infarction ventricular septal rupture

A 59-year-old man, who had been treated using the infarction exclusion technique for inferior post-infarction ventricular septal rupture (VSR) 4 months previously, was readmitted because of deterioration of mitral valve regurgitation, residual shunt, and progression of pulmonary hypertension. We performed mitral valve replacement via the transseptal approach, patch closure of the defect via the transtricuspid approach, and tricuspid valve annuloplasty. The post-operative course was uneventful. The transtricuspid approach is useful in redo surgery for post-infarction VSR.     

Cardiovascular effects of flunitrazepam (rohypnol, RO-5-4200) (author's transl)]

We reported on the haemodynamic effects of 0.03 mg/kg flunitrazepam during surgical procedures in neuroleptanalgesia in 39 patients with congenital or acquired heart diseases, functional class II-IV. The benzodiazepine derivative did not cause any relevant effect on the inotropic state of the myocardium. There were only minor changes in cardiac index, stroke index, right and left atrial pressure. Changes in arterial pressure and left ventricular pressure during and immediately after surgical procedures, and in arterial perfusion pressure during extracorporeal circulation, as well as an only short lasting increase in heart rate were demonstrative a peripheral vasodilator effect. The decrease in ventricular work and myocardial oxygen consumption are of value in patients with coronary heart disease, especially immediately after surgical procedures. Flunitrazepam is considered an additional drug during neuroleptanalgesia, when hypertension is causing some problems.     

Circulatory effects of isoflurane during acute hypercapnia

Acute respiratory acidosis results in increases in cardiac output and in systemic and pulmonary arterial blood pressures. The aim of this investigation was to determine if isoflurane modifies these effects. Nine patients (ASA II or III) scheduled for major surgery took part in the investigation. After the induction of general anesthesia, CO2 was added to the inspiratory gas mixture. After 15 min, ventilation with addition of CO2 (PaCO2 8-9 kPa) isoflurane (3%) was added. Hemodynamic measurements were made to study the effects of acute hypercapnia and the effects of isoflurane during hypercapnia. The addition of carbon dioxide resulted in increases in cardiac output, systemic and pulmonary arterial blood pressures, and right and left ventricular stroke work. The addition of isoflurane during hypercapnia decreased systemic arterial blood pressure, but pulmonary arterial blood pressure was unaffected, cardiac output and stroke volume did not change, and left but not right ventricular stroke work decreased. In conclusion, acute pulmonary hypertension induced by hypercapnia was not affected by isoflurane but, despite increased right ventricular stroke work, there were no signs of right ventricular failure.     

Current surgical strategy for post-infarction left ventricular aneurysm--from linear aneurysmecomy to Dor's operation.

The surgical strategy for left ventricular (LV) aneurysm after myocardial infarction has been changing recently. Conventionally, linear aneurysmectomy has been widely performed as a standard procedure for post-infarction LV aneurysm. However, this technique remains unsatisfactory because LV distortion occurs postoperatively and an akinetic or dyskinetic area persists in the ventricular septum, resulting in limited improvement of cardiac function. To overcome these problems, Dor and associates excluded all akinetic or dyskinetic myocardium from the left ventricle including the septum and placed a tight circumferential suture around the aneurysmal base to reduce the LV volume and return the LV contour to near normal (endoventricular circular patch plasty: EVCPP). As an alternative to conventional linear aneurysmectomy, EVCPP (Dor's operation) is now being performed more widely for the treatment of post-infarction LV aneurysm, and it achieves better postoperative cardiac function. Recently, EVCPP has attracted interest as a treatment for post-infarction large akinetic scars and ischemic cardiomyopathy (ICM), both of which have a poor prognosis. In this article, based on the author's clinical experience and on the literature, EVCPP is reviewed with respect to its indications for patients with post-infarction LV aneurysm or large akinetic scars, and pointers and results for this technique are discussed.     

Inhaled epoprostenol (prostacyclin) and pulmonary hypertension before cardiac surgery

OBJECTIVE: Pulmonary hypertension is commonly found in patients undergoing valvular surgery and can be worsened by cardiopulmonary bypass. Inhaled epoprostenol (prostacyclin) has been used for the treatment of pulmonary hypertension, but its effects compared with those of placebo on hemodynamics, oxygenation, echocardiographic examination, and platelet function have not been studied during cardiac surgery. METHODS: Twenty patients with pulmonary hypertension undergoing cardiac surgery were randomized in a double-blind study to receive inhaled epoprostenol (60 microg) or placebo. The inhalation occurred after induction of anesthesia and before surgical incision. The effects on left and right systolic and diastolic cardiac functions evaluated by means of pulmonary artery catheterization and transesophageal echocardiography, as well as oxygenation and platelet aggregation, were studied. RESULTS: Inhalation of epoprostenol significantly reduced indexed right ventricular stroke work from 10.7 +/- 4.57 g. m. m(-2) to 7.8 +/- 3.94 g. m. m(-2) (P =.003) and systolic pulmonary artery pressure from 48.4 +/- 18 mm Hg to 38.9 +/- 11.9 mm Hg (P =.002). The effect was correlated with the severity of pulmonary hypertension (r = 0.76, P =.01) and was no longer apparent after 25 minutes. There was no significant effect on systemic arterial pressures, left ventricular function, arterial oxygenation, platelet aggregation, and surgical blood loss. CONCLUSION: Inhaled epoprostenol reduces pulmonary pressure and improves right ventricular stroke work in patients with pulmonary hypertension undergoing cardiac surgery. A dose of 60 microg is hemodynamically safe, and its effect is completely reversed after 25 minutes. We did not observe any evidence of platelet dysfunction or an increase in surgical bleeding after administration of inhaled epoprostenol.     

First pulmonary valve replacement with Freedom Solo stentless valve in an adolescent. A case report

Tetralogy of Fallot (TOF) is a common form of cyanotic heart disease. Complete surgical correction in younger age group offers good long-term results with reasonable morbidity and improved prognosis in patients with TOF. However, following corrective surgery pulmonary valve replacement (PVR) might be required for residual pulmonary regurgitation in order to avoid irreversible right ventricular remodeling. Otherwise, residual uncorrected pulmonary regurgitation may lead to right ventricular dilatation, impaired biventricular function, ventricular arrhythmias and limited exercise capacity. We report the first case of Freedom Solo stentless valve (Sorin Group, Saluggia, Italy) implantation in the pulmonary position in an adolescent with severe pulmonary insufficiency 12 years after the repair of TOF. Pericardial stentless valves may be an alternative choice for pulmonary valve replacement to improve right ventricular contractile recovery and remodeling after PVR and may have impact on long-term survival.     

Acute pulmonary hypertension causes depression of left ventricular contractility and relaxation

BACKGROUND AND OBJECTIVE: The haemodynamic effects of acute pulmonary hypertension can be largely attributed to ventricular interdependence during diastole. However, there is evidence that the two ventricles also interact during systole. The aim of the present study was to examine the effects of acute pulmonary hypertension on both components of left ventricular systole, i.e. contraction and relaxation, using load-independent indices. METHODS: Ten pigs were instrumented with biventricular conductance catheters, a pulmonary artery flow probe and a high-fidelity pulmonary pressure catheter. Haemodynamic measurements were performed in baseline conditions and during stable pulmonary vasoconstriction induced by the thromboxane analogue U46619. Contractility was quantified using the end-systolic pressure-volume and preload recruitable stroke work relationships. The tau-end-systolic pressure relationship was used to assess load-dependency of relaxation. RESULTS: Acute pulmonary hypertension caused a decrease in the slope of the left ventricular preload recruitable stroke work relationship (from 6.64 +/- 1.7 to 5.19 +/- 1.9, mean +/- SD; P < 0.05), a rightward shift of the end-systolic pressure-volume relationship (P < 0.05), and an increase in the slope of the tau-end-systolic pressure relationship (from -0.15 +/- 0.5 to 0.35 +/- 0.17; P < 0.05). The diastolic chamber stiffness constant of both ventricles increased during pulmonary hypertension (P < 0.05). CONCLUSIONS: In the present model, acute pulmonary hypertension impairs left ventricular contractile function and relaxing properties. The present study provides additional evidence that, besides the well-known diastolic ventricular cross talk, systolic ventricular interaction may play a significant role in the haemodynamic consequences of acute pulmonary hypertension.     

Haemodynamic Effects of Combined Nitroglycerin- and Dobutamine-Infusions After Coronary By-Pass Surgery With One Nitroglycerin-Related Complication

The haemodynamic effects of separate and simultaneous nitroglycerin (NTG) - and dobutamine (DOB) infusions were determined in order to evaluate the nature of the effects of combined treatment. Ten patients were studied, 6 h after coronary by-pass surgery. NTG alone reduced significantly systemic and pulmonary arterial, as well as ventricular filling pressures, and brought about a concomitant 10% decrease in the cardiac index (P<0.05). Dobutamine (6 μg/kg/min) did not affect systemic or pulmonary arterial pressures, nor ventricular filling pressures. As a result of the 20 beats/min rise in heart rate produced by DOB, the cardiac index was increased by 24%, whereas the stroke volume and work indices remained unchanged during DOB-infusion. The haemodynamic changes brought about by either NTG or DOB separately were unaffected by the simultaneous infusion of the other vasoactive drug. The haemodynamic effects of the combined treatment were simply the sum of their separate effects, thereby yielding reduced arterial and ventricular filling pressures, increased heart rate, and slightly augmented cardiac index with significantly reduced systemic vascular resistance; myocardial oxygen consumption was unaffected by the combination therapy. One patient, whose case is discussed separately, had a hypotension-bradycardia complication during NTG-infusion.     

Comparison of cardiac function in surgically corrected and congenitally corrected transposition of the great arteries

The capacity of the anatomic right ventricle to sustain normal function against systemic pressure long after atrial baffle procedures in patients with complete transposition of the great arteries remains unknown. Pulmonary and systemic ventricular function was measured by first-pass radionuclide studies in 11 children 7 +/- 3 years (+/- standard deviation) after baffle procedures. For comparison, similar measurements were made in eight patients with isolated congenitally corrected transposition of the great arteries and in 10 children in a control group. Exercise increased heart rate and cardiac index to similar levels in all three groups. Ventricular volumes were greater than control volumes in both groups with congenital heart disease. Exercise increased pulmonary ventricular ejection fraction in the control and congenitally corrected groups, but not in the surgically corrected group. Systemic ventricular ejection fraction increased during exercise in the control group, but remained unchanged in both transposition groups. These results show that cardiac index during exercise is maintained in patients after baffle procedures for complete transposition of the great arteries. However, pulmonary and systemic ventricular ejection fractions fail to increase with exercise, and ventricular volumes are markedly greater than normal.     

Operative therapy of malignant ventricular rhythm disturbances

Pre- and postoperative electrophysiologic study (EPS), intraoperative cardiac mapping, and extended endocardial resection of scar (EER) has enabled us to identify subgroups among 94 patients who have had operation to control or prevent malignant ventricular arrhythmia. Operative mortality was 8.5% and cure or prevention of ventricular arrhythmia was accomplished in 92% of survivors. Group 1: 13 patients were resuscitated from "sudden death" due to ventricular fibrillation (VF). All had exercise-induced VF and/or ventricular tachycardia (VT). Preoperative EPS revealed no inducible VT/VF. All had coronary artery disease, without evidence of myocardial infarction (MI) or ventricular wall motion abnormality; all were cured with conventional myocardial revascularization. Group 2: 65 patients had MI with residual left ventricular wall motion abnormality, usually aneurysm. The malignant arrhythmia, either sustained VT (38 patients) or VF (27 patients), was inducible by EPS but not usually by exercise, and all were refractory to medical therapy. Treatment was operative mapping, aneurysmectomy, EER, and coronary revascularization. Operative mortality was 11.9%; 90% of survivors are arrhythmia free, off drugs; 10% are now drug responsive. Group 3: 3 patients without coronary disease had VT or VF caused by endocardial sarcoidosis or operative scar from a previous congenital heart operation. Treatment was EPS, operative mapping, and excision of abnormal endocardial scar with no operative mortality. Group 4: 13 patients underwent aneurysmectomy for indication other than arrhythmia, but had preoperative ventricular irritability which was not life-threatening. Operation was aneurysmectomy, prophylactic EER, and revascularization with no mortality and no postoperative arrhythmic events. After many years of unpredictable and unsatisfactory results from various empirical surgical approaches, the operative treatment of malignant ventricular arrhythmia is now based on sound electrophysiologic principles.