Posterior ventricular aneurysm, severe mitral regurgitation, and rupture of the left ventricle after acute myocardial infarction: six-year survival after surgical correction.

Posterior ventricular aneurysm and severe mitral regurgitation due to acute myocardial infarction are rarely recognized during life. This report describes the successful surgical treatment of a patient with this combination of lesions who at operation was found to have rupture of the left ventricle as well. Aneurysmectomy, mitral valve replacement, and coronary artery bypass were performed with a gratifying late result. Aggressive investigation of patients with hemodynamic deterioration after posterior myocardial infarction may identify surgically correctable mechanical complications.     

A New Operation for Far-Advanced Cystic Medial Necrosis of the Aortic Root

Three patients with far-advanced cystic medial necrosis of the aorta, which had produced giant bulbous enlargement of the aortic root and severe aortic regurgitation, were operated on using a procedure not previously described. Measurements of the aortic valve annulus and ascending aorta were made from aortograms. A knitted polyester arterial prosthesis was sewn together to form a circle. This circular prosthesis was sewn to a 31 mm Björk-Shiley aortic valve prosthesis in the way that a tire is fitted onto a wheel. The resulting composite prosthesis, which had the same diameter as the aortic root, was used to replace the excised valve. In all cases a composite prosthesis measuring greater than 50 mm in diameter was used. In 2 of the 3 patients the ascending aorta was replaced with a tubular graft reshaped as a truncated cone. This reshaping was done by inserting multiple gussets into one end of the aortic prosthesis so that the flanged end fit precisely to the enlarged valve prosthesis and the other end fit precisely to the transverse aortic arch. Two patients are asymptomatic more than two years following operation. The third patient died suddenly of a ventricular arrhythmia on the twenty-third postoperative day.     

A simple, safe, and rapid technique for the management of recurrent coarctation of the aorta

Six patients treated in infancy for coarctation of the aorta developed severe stenosis of the end-to-end aortic anastomosis that produced marked collateral circulation and upper extremity hypertension. Operation relieved the anastomotic obstruction in all 6 patients. A resection of the stenotic anastomosis with end-to-end aortic anastomosis was performed in 2 patients, bypass grafting between the transverse aortic arch and the distal aorta was done in 3 patients, and bypass grafting between the enlarged left subclavian artery and the distal aorta was performed in 1 patient. Interposed graft segments were short and had a diameter equal to or greater than the diameter of the aorta above or below the stenosis. Insertion of such short graft segments over an anastomotic obstruction provides an easy, rapid, and safe method for relieving hypertension and restoring distal pulsatile blood flow. Bypass grafting should be reserved for patients in whom anatomical considerations present an unusual hazard for a second aortic resection.     

The elimination of periprosthetic leaks as a complication of mitral valve replacement

A technique for placement of a mitral valve prosthesis has been designed specifically to eliminate the development of periprosthetic leak as a complication of mitral valve replacement. This technique has been employed in 97 patients undergoing isolated mitral valve replacement. No incidents of periprosthetic leak have been discovered in this group, despite a careful search for the complication.This group of patients is compared to an earlier group in whom mitral valve replacement was performed using more common techniques. A 10% incidence of periprosthetic leak was found in this group. Periprosthetic leaks commonly cause severe congestive heart failure or pronounced anemia from excessive hemolysis. Reoperation for the repair of periprosthetic leaks has been associated with a high mortality. These leaks are regarded as a technical error and may be avoided by an appropriate change in the technique of mitral prosthesis insertion.     

Multiple Valve Replacement: Changing Status

Review of our experience with multiple valve replacement over a 6-year period revealed a recent marked reduction in operative risk. Operative mortality for 62 patients operated on before 1974 was 34%; for 44 patients operated on since 1974, mortality was only 11%. In both groups, mortality was clearly related to the preoperative cardiac functional status. Several recent technical advances including myocardial protection by topical hypothermia, shortened perfusion time, and the intraaortic balloon pump may all have contributed to the reduced operative risk.     

Transbronchial Catheterization of Pulmonary Abscesses

A major indication for bronchoscopy in patients with pulmonary abscess is the need to establish adequate drainage. Often, associated bronchial swelling precludes direct entry into the cavity with standard suctioning devices. Satisfactory drainage may require numerous bronchoscopic procedures, prolonging hospitalization and subjecting the patient to the complications of pyogenic pulmonary abscess. We have recently adopted the technique of passing angiography catheters through the rigid bronchoscope into the abscess cavity, thereby facilitating the bacteriological diagnosis and drainage of the cavity.     

Reconstructive valve surgery.

Despite continued refinement of heart valve prostheses, valve replacement carries risks of thromboembolic, mechanical, and infectious complications, and long-term success is further limited by the eventual wear of prosthetic parts. In many patients with congenital or acquired valve diseases, valve function may be improved, if not restored, by reconstructive techniques, prosthetic replacement being thereby avoided or delayed. This review examines the current status of reconstructive procedures for management of diseased valves, with emphasis on long-term results and post-operative hemodynamic studies. In many instances the choice between reconstruction and replacement of a diseased valve remains controversial. The documented success of selectively applied reconstructive techniques, however, weighs against expedient decisions for prosthetic replacement and supports a continuing search for new techniques.     

Experimentally reversed pulmonary blood flow. Implications for the surgical management of complex forms of congenital heart disease.

Blood flow to the right lung was reversed in 28 dogs, 14 of which survived more than 1 month. Four successful long-term survivors (1 years to 4 years 7 months) were repeatedly studied by cardiac catheterization, angiography, and ventilation/perfusion scans as well as hemodynamically when they were killed. Hemodynamics and gas transfer were normal up to 4 1/2 years after the procedure, and the histology of the right lung was essentially normal. The application of reversed pulmonary blood flow is proposed in the surgical management of forms of congenital heart disease in which the right ventricle is diminutive. The procedure consists of repartitioning of the atria to allow venous blood to flow into the lung through the pulmonary veins and exit to the left atrium through the pulmonary artery.     

Pharmacological Preservation of the Ischemic Heart

This study was based on the concept that intracellular accumulation of calcium plays a role in mediating ischemic myocardial injury and that inhibition of entry of calcium into cells may have a salutary effect on the ischemic heart. Nifedipine, a potent vasodilator and inhibitor of transmembrane calcium flux, was infused into the aortic root of 6 dogs (5 μg/kg/hr) during 2 hours of myocardial ischemia while on cardiopulmonary bypass. Seven control animals received normal saline at the same flow rate and temperature (20°C).The results showed that none of the 7 control animals were able to maintain adequate aortic pressure or cardiac output after 30 to 60 minutes of normothermic reperfusion. All had marked left ventricular failure and were unresponsive to large doses of inotropic agents. In contrast, the 6 dogs treated with nifedipine were weaned from bypass either without difficulty or requiring small doses of calcium chloride and norepinephrine. Light microscopy demonstrated more marked ischemic damage in the control group than in the group of drug-treated dogs. We conclude that the concept of inhibition of transmembrane calcium flux offers a new and potent method for myocardial preservation during ischemia.     

Late clinical problems with Beall model 103 and 104 mitral valve prostheses: hemolysis and valve wear.

The purpose of this study was to determine the influence on hemolysis of the spatial orientation of the struts in the Beall mitral valve prosthesis, Models 103 and 104. Thirteen pairs of patients were selected to match struts oriented parallel and perpendicular to the left ventricular outflow tract axis. The average time after operation was 3.73 years. Complete blood counts and relative serum chemistry values were determined.     

Symptomatic Methemoglobinemia with a Commonly Used Topical Anesthetic,Cetacaine

Severe cyanosis resulting from acquired methemoglobinemia after application of a topical anesthetic, Cetacaine spray, occurred in a 37-year-old patient following bronchoscopy for postoperative atelectasis. Response to methylene blue therapy was dramatic and complete. Attention is drawn to a dangerous adverse effect of this commonly used topical anesthetic agent.     

Durability of Prosthetic Heart Valves

Accelerated fatigue testing of clinical heart valves has been performed at cyclic rates of 33 to 35 cycles per second at 37° using water for non-biological valves and glutaraldehyde solutions for tissue valves. Flows were in the physiological range, and the pressure difference across each valve during closure was 100 ± 25 mm Hg. The results showed that major fatigue occurred for the Starr-Edwards 2320 at 150 million cycles, the Hufnagel trileaflet at 124 million cycles, the Björk-Shiley Delrin disc at 140, the Björk-Shiley Pyrolite disc at 973, the Beall 103 at 60, the Hancock porcine at 62, the Carpentier-Edwards porcine at 34, and the Ionescu-Shiley porcine pericardial prosthesis at 65 million cycles. The Lillehei-Kaster was removed after 762 million cycles without discernible wear.Three facts emerged from the testing data: (1) the component worn in vitro wears in vivo; (2) the sites of in vitro fatigue on the component are identical to clinical specimens; and (3) those valves that have high durability in vitro have given similar performance in patients. The in vitro and clinical data for tissue valves do not correlate. The possible reasons for the discrepancy are discussed, and a note of caution is made regarding realistic expectations of clinical durability of tissue valves.     

Nutrient pathways to flexor tendons using hydrogen washout technique

The nutrient pathways of flexor tendons within the flexor sheath were studied using the hydrogen washout technique. Hydrogen uptake and decay of a free segment of flexor tendon detached from its blood supply were not significantly different from an intact tendon lying in the synovial bed. There was no hydrogen uptake by flexor tendons which were mechanically separated from the synovial bed, even though muscular, periosteal and vincular attachments were intact. We concluded from this study that the synovium of the flexor tendon was a significant nutrient pathway for the flexor tendon and that the blood vessels did not appear to play a significant role in the nourishment of the flexor tendon.     

Myocardial Preservation with Nifedipine: A Comparative Study at Normothermia

Sixty-four dogs were placed on normothermic total cardiopulmonary bypass, and global ischemia was induced for 1 hour during which continuous infusions (240 ml per hour) (N = 39) or bolus injections (150 to 200 ml every 30 minutes) (N = 23) into the proximal aortic root were performed. The control groups (N = 26) had infusion or injection of normal saline solution, normal saline solution + 25 mEq/L of potassium chloride, or Normosol-R pH 7.4. The cardioplegic solution (N = 15) contained 25 mEq/L of potassium chloride in Normosol-R pH 7.4, 0.25 mg/ml of lidocaine, 500 mg/dl of glucose, and 1.8 μ;/ml of insulin. The nifedipine group (N = 23) had infusion or injection of 0.167 to 0.2 μ;g/ml of nifedipine in saline solution, Normosol-R pH 7.4, or the cardioplegic solution.Left ventricular performance was assessed by phasic and mean measurements of left ventricular peak and end-diastolic pressures and its first derivative, left and right atrial pressures, and ascending aortic blood flow. Calculations of stroke work index and total peripheral resistance were performed. Morphological examinations, and light and electron microscopic examinations of heart slices were done. The results demonstrated a consistent superiority of the nifedipine group in terms of performance after bypass compared with the cardioplegic or control group. Normal preischemic stroke work indices and Sarnoff curves were present 2 hours after bypass for the nifedipine-treated groups. The cardioplegic solution was ineffective when given continuously but gave modest protection when given as a bolus injection. It is concluded that the concept of the efficacy of calcium blockade during ischemia and the initial reperfusion period for enhanced myocardial protection is valid.