Stanley K. Brockman

Cardiac Surgery in Nonagenarians

Abstract Objectives and Background: The purpose of this study was to document our initial experience with patients 90 years of age and older and to determine whether cardiac surgery is justified in this age group. Cardiac surgery in octogenarians has proven to be a successful and worthwhile procedure. A small group of nonagenarians with severe coronary artery disease (CAD) and aortic valve disease refractory to medical therapy have been considered for surgery. Methods: Fourteen patients aged 90 or more underwent cardiac surgery for symptomatic CAD or aortic valvular disease refractory to medical therapy. Eight patients underwent isolated coronary artery bypass grafting (CABG) and six patients underwent aortic valve replacement (AVR). All patients were in NYHA Class IV preoperatively. Results: Hospital mortality occurred in one patient (7%). Hospital morbidity occurred in 10 patients (71%) and included 7 cardiac, 5 neurological, 1 gastrointestinal, 1 infectious, and 1 pulmonary event. All survivors left the hospital symptomatically improved. The mean length of stay was 26 days. Four CABG patients went on to die at a mean of 2 years and 2 months, and 3 remain alive at a mean of 2 years and 4 months. Three AVR patients expired at a mean of 3 years and 4 months, and 3 remain alive at 4 years and 1 month. Conclusions: Cardiac surgery in carefully selected nonagenarians is justified and can be performed with acceptable results.

Coronary Artery Bypass Surgery in Nonagenarians

As the number of nonagenarians increases yearly in the United States, surgeons will be asked more often to evaluate the possibility of intervention for coronary artery disease in this age group. The purpose of this study is to document experience with patients 90 years of age or older in order to determine whether coronary artery bypass grafting surgery is justified. Eleven patients aged 90 years or more underwent cardiac surgery for symptomatic coronary artery disease refractory to medical management between January 1, 1987, and December 31, 1996. All patients were in NYHA Class IV preoper atively. In-hospital death occurred in two patients (18%). In-hospital morbidity occurred in all patients (100%) including seven cardiac, four respiratory, two neurologic, and one infectious. All survivors left the hospital symptomatically improved. The mean length of stay was 28 days. Four patients died at a mean of 2 years and 2 months post operatively. Five patients remain alive at a mean of 1 year and 7 months. Coronary artery bypass grafting in nonagenarians can be performed successfully in selected cases. However, increased mortality and morbidity rates and length of stay are associated with this age group. For survivors, the quality of life is improved and the projected life expectancy restored.

Temporary epicardial atrial pacing electrodes: duration of effectiveness based on position.

BACKGROUNDnTo investigate the duration of effectiveness in the postoperative period of temporary epicardial atrial pacing electrodes on the right atrium, based on position.nnnMETHODSnThe function of temporary epicardial atrial pacing electrodes were examined in 55 patients undergoing coronary artery bypass grafting from March 20, 1996, to July 31, 1996, at Allegheny University Hospitals, Hahnemann Division, Philadelphia, PA. There were 41 male and 14 female patients. The mean age was 71 years (range 35 to 86 years). Two atrial and two ventricular temporary epicardial pacing electrodes were placed at the termination of cardiopulmonary bypass. One atrial electrode was placed on the body of the right atrium at the junction of the superior vena cava (body electrode); the other was passed through the pursestring of the atrial cannulation site (appendage electrode).nnnRESULTSnThe mean thresholds for the atrial body electrodes on the operative day and postoperative days 1 and 2 were 4.96, 6.67, and 6.80 mA, respectively. The mean thresholds for the atrial appendage electrodes were 5.98, 7.50, and 8.59 mA, respectively.nnnCONCLUSIONSnTemporary epicardial atrial pacing electrodes are more effective when the wires are placed in the atrial body of the right atrium than if they are wrapped within the pursestring of the right atrial appendage. As a result of these findings, the common practice of placing the pacing wire through pursestring tissue should be abandoned.

POSTPARTUM CORONARY ARTERY DISSECTION : EMERGENCY CORONARY ARTERY BYPASS WITH VENTRICULAR ASSIST DEVICE SUPPORT

Acute myocardial infarction during pregnancy and in the puerperium is a rare event: the incidence ranges from 1 per 10,000 to 1 per 30,000 deliveries. Although the etiology is unknown, the pathology may involve thrombosis, spasm, or dissection of the coronary artery. We present the case of a 34-year-old white woman who presented to our institution in cardiogenic shock after an acute myocardial infarction 2 weeks postpartum. This case reinforces the concept that postpartum coronary artery dissection is a fatal disorder. We were able to successfully support the myocardium and the end-organs with a ventricular assist device. We performed concomitant coronary artery bypass grafting in an attempt to salvage the remaining myocardium. Management with emergency coronary revascularization and ventricular assist device support is described.

Amiodarone-associated hemoptysis.

Amiodarone is a benzofuran derivative with a chemical structure similar to thyroxine. Originally introduced to treat angina pectoris, amiodarone was found to have antiarrhythmic properties, and in 1985, was approved in the United States for treatment of life-threatening ventricular arrhythmias. It is now used for various ventricular and supraventricular arrhythmias refractory to conventional first-line medications, and as a result, side effects have been observed with increased frequency. The most severe and potentially life-threatening of these side effects is the development of pulmonary toxicity. Typically, amiodarone pulmonary toxicity (APT) is manifested by acute pneumonitis and chronic fibrosis. Amiodarone-associated hemoptysis (AAH) is a rare occurrence. The authors describe a case of AAH successfully treated with cessation of drug and steroid therapy.

Intramyocardial Regulation of Coronary Dynamics

The intramural blood vessels and fluid-filled interstitial space form a hydraulic continuum enmeshed by myocardial muscle layers and collagen matrix. An underlying theoretical and conceptual construct presented here emphasizes the dynamic interplay between interstitial and intravascular compartments and the resultant microvascular resistance in response to extravascular changes, be these hydraulic, connective tissue (collagen) dependent, or intramyocardial fiber stress in origin. The lumenal patency or narrowing of the coronary resistance vessels depends, in part, on the supporting structure of the myocardium, mediated through collagen matrix attachments (tethering) and interstitial fluid (hydraulic skeleton) matrix. Both these architectural structures provide scaffolding that supports muscle cells and blood vessels. Multiple interactions, including fluid transport, at the vessel-interstitiummuscle interface level are principally responsible for the mechanical regulation of coronary flow dynamics. Analysis of the intramyocardial mechanical milieu in terms of solid elastic theory concepts can be misleading. By exploring the spectrum (beating-isobaric, isovolumic; arrested-systolic, diastolic) of intramyocardial mechanical states, an impetus for a more definitive framework characterizing coronary physiology may emerge.

Pharmacological Criteria for Ventricular Assist Device Insertion Following Postcardiotomy Shock: Experience with the Abiomed BVS System

Aim:Thetraditional approach to postcardiotomy shock includes inotropic support followed by the application of an intra‐aortic balloon pump (IABP). Consideration toward insertion of a ventricular assist device (VAD) becomes necessary when these maneuvers fail to restore hemodynamic stability. The definition of maximal inotropic support, however, is lacking such that a standard formula for VAD insertion remains problematic. The purpose of this paper is to define the pharmacological thresholds for VAD implantation in the setting of postcardiotomy cardiogenic shock. Methods: The medical records of all adult open‐heart operations performed at Hahnemann University Hospital, Philadelphia, PA, from 1 July 1996 through 1 July 1999 were reviewed. Specific data were collected on the hernodynamics and inotrope levels upon separation from cardiopulmonary bypass (CPB). The hospital course was reviewed with attention toward documenting hospital mortality. Cardiogenic shock was defined as systolic blood pressure (SBP) < 100 mmHg, mean pulmonary artery blood pressure (mPAP) > 25 mmHg, central venous pressure (CVP) > 15 mmHg, and cardiac index (CI) < 2.0 L/min/per m2. lnotrope dosages were defined as low, moderate, and high according to assigned values.* A formula for VAD insertion was established if cardiogenic shock parameters were present in the setting of two or more high dose inotropes. Early VAD insertion was defined as implantation within three hours of the first attempt to wean from CPB. The VAD recipients were divided into two groups. Group A were VADs placed in conjunction with the formula. Group B was VADs placed in violation (excess) of the formula. The results of these two groups were compared.

Myocardial protection: an expanding or contracting discipline?

For the past thirty years cardiac surgeons have had a unique opportunity to study the consequences of myocardial ischemia and reperfusion. With the advent of an ability to intervene in acute myocardial syndromes, cardiologists have vigorously joined that effort as have fundamental scientists. Exogenous myocardial protective strategies have emerged as have novel strategies that take advantage of endogenous mechanisms of myocardial protection. As a consequence of improved myocardial protection, operative mortality and morbidity, in particular the low output syndrome, have diminished. However, despite important increases in the knowledge base referable to myocardial ischemia and reperfusion, major advances in myocardial protection have slowed in the past several years. This article explores potential untapped options for augmenting myocardial protection and focuses on the potential adverse interactions between cardiopulmonary bypass and myocardial protection as a prime target for future investigations leading to improved myocardial management during heart operations.