Influence of length of aortic occlusion with cold potassium cardioplegia on early and late mortality in cardiac valve replacement.

This study determines if prolonged aortic crossclamp time (ACC) with the use of cold potassium cardioplegia during elective cardiac valve replacement contributed to the risk of operative mortality in 225 patients. In Group I (143 patients), the ACC was less than 120 minutes (mean 86) and in Group II (82 patients), it was greater than 120 minutes (mean 146). The preoperative variables showed that Group II contained more severely ill patients who were undergoing more complex operations than in Group I. The operative mortality rate was 7% in Group I and 10% in Group II (p = not significant). Postoperative inotropic support was required in 13% of Group I and 30% of Group II patients (p less than 0.005). Operative mortality in patients in New York Heart Association (NYHA) functional class I and II was 0 and in patients in classes III and IV it was 13% (p less than 0.00008). Five percent of patients in NYHA classes I and II and 32% in classes III and IV required inotropic support (p less than 0.000005). The actuarial survival at 60 months was 88 +/- 3% for Group I and 77 +/- 7% for Group II (NS). For the NYHA class I and II patients, however, it was significantly better (98 +/- 2%) than class III and IV patients (75 +/- 5%) (p less than 0.0001). Analysis by logistic equation revealed that the NYHA functional classes III and IV were significant incremental risk factors for probability of in-hospital mortality (p less than 0.0001) but not the ACC time (p greater than 0.1).(ABSTRACT TRUNCATED AT 250 WORDS)

Transvenous atrial pacing with a new electrode.

The unique concept of an atrioventricular electrode is presented. This transvenous electrode is incorporated into one body and has the mechanical advantages of double fixation and atrial or ventricular sensing or pacing. With the "extension wire principle," it can be used for diagnostic or therapeutic purposes, short- or long-term pacing. The optimal pacemaker setting can be adjusted according to the individual needs of the patient and can easily be converted to a permanent system. This atrioventricular electrode was used for long-term atrial pacing in 4 patients with tachyarrhythmia syndrome. There were no electrode-related complications. Atrial pacing was maintained in all patients. The longest follow-up period was 2 1/2 years.

Hemodynamic consequences of bronchial flow during cardiopulmonary bypass.

Nine patients (seven men and two women) were studied while undergoing coronary artery bypass on cardiopulmonary bypass. Selective bronchial flow samples were obtained and analyzed for prostaglandin E2 levels, and the hemodynamic effects of this vasodilator were studied. Bronchial flow collection and measurements were performed during hypothermic cardioplegic arrest while the peripheral anastomosis was being completed, as described previously. This collected sample was reinfused abruptly to the pump circuit, but samples were also analyzed for specific radioimmunoassay antiserum for prostaglandin E2 levels. Urine levels were obtained both with and without indomethacin block. All nine patients were studied for the hemodynamic effects of rapidly reinfused bronchial flow. A 34% +/- 8.8% mean drop of blood pressure and peripheral vascular resistance were recorded (p less than 0.002). Three study groups were established: In Group I, serum prostaglandin assay was performed on six patients. Prostaglandin E2 levels showed an average of increase of 159% compared to the baseline (p less than 0.02). In Group II, urine prostaglandin was measured. Nine assays were performed on six patients. Analysis of the total urine production while on cardiopulmonary bypass showed an average increase in prostaglandin E2 of 300% (p less than 0.02). In Group III, combined serum and urine prostaglandin levels were measured in three patients before and after indomethacin block (50 mg four times a day for 48 hours before the operation). All of these patients demonstrated the same hypotensive phenomena with reinfusion of the bronchial flow. The urinary prostaglandin E2 output and serum prostaglandin E2 levels in bronchial flow were elevated. Overall, this group manifested a 50% reduction in prostaglandin E2 production over baseline values with indomethacin block (p less than 0.02) and a 300% increase in production during cardiopulmonary bypass (p less than 0.02). Our data suggest that significant amounts of prostaglandin E2 are released in the lung during the stress of cardiac operations. Rapid reinfusion of bronchial flow is responsible for hypotension during cardiopulmonary bypass. Pretreatment with indomethacin will not completely block prostaglandin E2 release in the lung during stress.

Intramyocardial calcification in the elderly. A diagnostic and therapeutic puzzle.

A 70-year-old woman presented with anular and progressive intramyocardial calcification within a five-year period. She had become increasingly symptomatic with mitral regurgitation and coronary insufficiency during the same period. The subvalvular (mitral) calcified intramyocardial mass was found to be "grumous atherosclerosis." This was obliterated while the mitral valve was replaced with a prosthetic valve and the coronary arteries were bypassed x3. She is surviving and well four years postoperatively.

Left ventricular laceration due to stented prosthesis.

Complications following open chest massage in patients with porcine xenografts in the mitral location have not been previously described. The authors report a case of cardiac resuscitation following mitral valve replacement with a stented porcine valve. The patient died following brief closed chest, and then, prolonged open chest, cardiac massage. Autopsy showed laceration of the left ventricle by the prosthetic valve stents. Physicians involved in the postoperative care of patients with stented prosthetic valves should be aware of this complication and should exercise caution when applying manual compression in the region of the posterolateral base of the heart.

Hemorrhagic infarction: A reperfusion injury following prolonged myocardial ischemic anoxia.

Sixteen canine myocardial pedicle preparations were divided into four groups. Group I received 60 minutes of reversible ischemic anoxia, Group II 90 minutes, Group III 120 minutes, and Group IV 180 minutes. Transmural ischemic infarction was present in Group I. With longer periods of anoxia, capillary disruption occurred, first in the subendocardium (90 minutes) and then transmurally (180 minutes). Reperfusion after ischemic, anoxic time periods of 90 minutes or greater produced hemorrhagic necrosis, the extent of which was directly proportional to the duration of the preceding ischemic, anoxic period. One hundred and twenty patients with aortic valve replacement surgery then were analyzed retrospectively. Of the 25 deaths, seven were due to immediate postinfarction, five from subendocardial hemorrhagic necrosis. The common factor in the patients with hemorrhagic infarction was a markedly reduced coronary flow (45 to 55 ml. per minute) for more than 70 minutes during the interval of cardiopulmonary bypass. Although other factors may be involved, it is hypothesized that the main cause is a degree of localized ischemia of sufficient duration to induce capillary disruption and subsequent postbypass hemorrhagic necrosis when normal coronary artery perfusion is resumed.

Selective intracavitary and coronary hypothermic cardioplegia for myocardial preservation.Clinical, physiologic, and ultrastructural evaluation.

Intraoperative myocardial protection was evaluated in two groups of patients undergoing coronary surgery in whom different techniques for cardiac arrest were utilized. In group A, profound selective myocardial hypothermic (15 to 18 C) arrest was achieved by perfusing a coolant (7 to 10 C) into the left ventricular cavity and the coronary circulation. The average anoxic arrest time was 82.5 +/- 27 minutes. In group B, ventricular fibrillation and moderate hypothermia were used. Group A patients showed rapid physiologic recovery, low average myocardial creatinine phosphokinase (MB-CK) isoenzyme levels (7.8 IU) , and a well-preserved myocardial ultrastructure. In group B, three patients showed abnormal physiologic recovery; six patients needed postoperative inotropic support; and in seven patients, electron-microscopy revealed irreversible focal changes. The average MB-CK isoenzyme level was 85.6 IU. Analysis of our data demonstrates that when myocardial protection during coronary bypass grafting is achieved by selective profound intracavitary and coronary cooling, there is physiological, ultrastructural, and biochemical evidence of less intraoperative myocardial damage than when ventricular fibrillation is applied.

Epicardial atrial pacing.

A modification of the technique for placing a permanent epicardial electrode to the atrium is described. It results in long-term atrial pacing and low sensing thresholds. The method requires meticulous surgical technique but is reliable, safe, and free from serious or long-term complications.

Pitfalls of undetected patent foramen ovale in off-pump cases.

We describe pitfalls of a hitherto undetected patent foramen ovale during the conduct of an off-bypass coronary revascularization. Manipulation of the heart resulted in right-to-left shunt and severe desaturation requiring institution of cardiopulmonary bypass to close the patent foramen ovale and complete the revascularization.

Decompression of the heart with siphon drainage.

A simple technique for inducing intracavitary hypothermic cardioplegia and decompressing the left heart through the ascending aorta is presented. The technique is based on siphon drainage, which eliminates the dangers of air embolism.

Circumferential intimal tear causing obstruction of the aortic arch: an unusual complication of aortic dissection.

A 66-year-old man was first seen because of occlusive disease of the aortic arch vessels secondary to a Type I aortic dissection. At operation, circumferential detachment of the intima was found with intussusception of this flap into the descending aorta causing obliteration of the arch vessels. There has been only one previous report of circumferential intimal intussusception complicating aortic dissection.

Pacemaker lead placement via a small cephalic vein.

The development of implantable defibrillators with single lead systems has necessitated the need for larger transvenous electrodes. This article describes a modified Seldinger technique that can be used when the cephalic vein is too small to allow passage of these larger leads. When successful, the procedure eliminates the need for direct needle cannulation of the subclavian vein and the accompanying risk of pneumothorax.

Intracavitary melanoma of the left atrium.

A 32-year-old man was seen with shortness of breath and increasing fatigue. Echocardiography revealed an intracavitary mass occupying the entire left atrium. The lesion was resected using cardiopulmonary bypass and found to be a large malignant melanoma. This case represents the rare occasion in which antemortem diagnosis of malignant melanoma within left atrium permitted successful palliative surgical resection. The patient is alive and active 6 months after operation.

Selective intracavitary and coronary profound hypothermic cardioplegia for myocardial preservation: a new technique.

A technique is described for selective intracavitary and coronary hypothermic perfusion during cardiac bypass with cardioplegia to facilitate cardiac operations. A cold perfusate (Plasmalyte 148 and mannitol, 12.5 gm/L at 8 degrees to 10 degrees C) is administered with the aid of a low-flow perfusion pump into the left ventricular cavity and coronary circulation through an apical perfusion-venting (Per-Vent) catheter. This perfusate cools the myocardium rapidly and homogeneously to a temperature of 15 degrees to 20 degrees C. Within this temperature range, complete cardioplegia occurs and the safe ischemia period can be extended to 120 minutes. This method was applied in 50 unselected consecutive adult patients undergoing aortocoronary saphenous vein bypass grafting or aortic or mitral valve replacement. All patients survived and had excellent recovery of ventricular function.

Improved cardiovascular hemodynamics with atrioventricular sequential pacing compared with ventricular demand pacing.

To determine the advantages of atrioventricular (AV) sequential pacing over ventricular demand pacing, paired cardiovascular hemodynamic studies were performed in each pacing mode at a constant heart rate. The paired studies included determination of ejection fraction (EF) by echocardiography and gated blood pool radionuclide scanning, and of cardiac output (CO) by the indicator-dilution method. There was no significant difference in EF with either pacing mode. Determined by echocardiography, EF with AV sequential pacing was 57% compared with 56% with ventricular demand pacing; by the gated blood pool method, EF with AV sequential pacing was 58% compared with 57% in the ventricular mode. Significant improvement with AV sequential pacing was seen in CO (4.75 L/min from 3.75 L/min; p less than 0.01); stroke volume (58 ml from 48 ml; p less than 0.02); arteriovenous oxygen content difference (4.9 vol% from 5.6 vol%; p less than 0.01); total peripheral resistance (1,724 dynes sec cm-5 from 2,025 dynes sec cm-5; p less than 0.01); and cardiac contractility, as reflected by mixing time (6.9 seconds from 8.0 seconds; p less than 0.02). No significant changes were noted in mean arterial or atrial pressure or in systemic oxygen consumption. In a second group of 6 patients, similar paired studies were done in AV sequential pacing modes before and after therapeutic reduction of total peripheral resistance. A significant increase in CO (43%) was observed following reduction in total peripheral resistance. We conclude that AV sequential pacing improves CO more effectively than ventricular demand pacing. Cardiac output can be further enhanced in patients with congestive heart failure by pretreatment with agents to reduce total peripheral resistance.

Pulmonary resection combined with cardiac operations.

Surgical management of patients with concomitant critical cardiac disease and resectable lung lesions is controversial. During a 7-year period (1982 to 1988), 21 patients underwent combined cardiac and pulmonary operations. Patients had cardiac symptoms only; the lung lesions were found on preoperative chest roentgenograms. The pathological diagnosis was established in only 2 of the patients before operation. All underwent concurrent pulmonary resection during cardiac operations requiring extracorporeal circulation. The pulmonary operations included 17 wedge resections and four lobectomies. The final diagnoses in 8 patients with stage I non-small cell lung cancer included epidermoid carcinoma (4), adenocarcinoma (3), and bronchoalveolar carcinoma (1). Postoperatively, 1 patient required a permanent pacemaker and 1 patient died. The actuarial survival at 5 years for all patients who underwent combined procedures was 95%. The 5-year survival for the 8 patients with lung cancer was 88% compared with 100% for those with benign pulmonary pathology (p = 0.172). This experience suggests that combining pulmonary resection with cardiac operations is safe and offers a favorable prognosis to a select group of patients.

Early and long-term effects on direct myocardial revascularization on cardiac function: a prospective study using multivariable physiological analysis.

Perioperative and late follow-up hemodynamic cardiovascular studies to assess the effects of direct myocardial revascularization on cardiac function objectively have been completed on 51 patients. Analysis of the data delineated three distinct groups basedon the patterns of their early postoperative recovery. Group I patients (12) had a hyperdynamic cardiovascular response to operation and returned to a normal physiological range of cardiac function within 24 hours. Group II patients (24) initially had moderate to severe myocardial decompensation postoperatively but responded to inotropic support and moved into the normal physiological range within 24 to 48 hours. Group III patients (15) had severe, prolonged myocardial decompensation with little response to inotropic support. There were no early deaths in Group I, 1 early iatrogenic death in Group II, and 2 deaths from sepsis, 1 in Group I and 1 in Group II. All 7 cardiogenic deaths occurred in Group III patients. Late follow-up studies 4 to 23 months postoperatively have been completed on 29 patients. These showed cardiovascular stability in the mean values in Groups I and II. Significant improvement in mean cardiac function was seen in surviving Group III patients.

Detection of creatine kinase BB isoenzyme in sera of patients undergoing aortocoronary bypass surgery.

Creatine kinase BB isoenzyme (CK-BB) was detected intraoperatively in 22 of 25 patients undergoing aortocoronary bypass surgery, both in the coronary sinus and in the mixed venous blood. In a group of 10 patients in whom selective intracavitary profound hypothermic arrest was used, CK-BB values were lower than in another group of 10 patients, in whom controlled ventricular fibrillation with moderate total body hypothermia was instituted. This latter group also had higher levels of CK-MB. Patients who developed acute myocardial infarction immediately prior to or during the surgical intervention had the highest CK-BB values. This enzyme appeared as early as 15 minutes after the institution of cardiopulmonary bypass and disappeared within 6 hours. It is considered that part of the BB isoenzyme in serum of patients undergoing heart surgery is of myocardial origin.

Minimally invasive coronary artery bypass grafting using the right gastroepiploic artery without pump.

OBJECTIVE: To explore the feasibility to operate on the right coronary artery and its branches utilizing the right gastroepiploic artery (RGEA) without cardiopulmonary bypass (CPB). All cases were performed since May 1996. METHODS: A small mid-line incision including splitting of the lower sternum gave excellent exposure. The inferior surface of the heart was dissected to expose and stabilize the target vessel. The heart rate was controlled with a Diltiazem drip. CPB was not necessary in any case. The right coronary artery was bypassed in four patients, the posterior descending artery branch in five patients and the terminal circumflex of the left coronary artery in one patient. After grafting, patency of the anastomosis was demonstrated by Doppler echocardiogram. RESULTS: No patient had perioperative mortality or complications. No patient had recurrent angina. Color Doppler echocardiographic imaging studies before discharge confirmed patency of the graft in eight of ten cases. In two cases, the gastroepiploic artery could not be visualized. Angiographic visualization was positive in four out of five cases. CONCLUSIONS: The gastroepiploic artery is an excellent conduit for vascularization of the inferior aspect of the heart. The operation can be done using a minimally invasive technique and without the use of cardiopulmonary bypass. This approach seems especially applicable in selective reoperative cases.

Elimination of cardiopulmonary bypass: a prime goal in reoperative coronary artery bypass surgery.

OBJECTIVE: The purpose of this study was to evaluate morbidity and mortality in reoperative coronary artery bypass surgery using the New York State database. METHODS: Patients undergoing reoperative coronary artery bypass between January-1995 and December 1996 were included. Patients were operated using cardiopulmonary bypass (CPB group, n = 184) or without cardiopulmonary bypass (non-CPB group, n = 105) by surgeon preference. Groups were compared for preoperative risk factors, postoperative mortality and major complications. RESULTS: Crude mortality was lower in the non-CPB group, despite a higher expected mortality, resulting in a risk-adjusted mortality of 1.3% versus 2.7% for the CPB group (NS). Of non-CPB patients, 91.4% were without complications, while only 72.1% of CPB patients (P < 0.0001) were complication-free. Major complications were significantly reduced in non-CPB patients compared to CPB patients: stroke 0% versus 3.8% (P < 0.04), cardiovascular complications 4.8% versus 15.8% (P < 0.005), other major complications 1.9% versus 10.4% (P < 0.007). Postoperative IABP support was needed in 1.9% of the non-CPB group patients and in 14.2% of the CPB group (P < 0.0007). CONCLUSIONS: The main object of reoperative CABG is to relieve symptoms, since the survival benefit of the procedure has not been demonstrated. Performance of reoperative coronary artery bypass surgery without cardiopulmonary bypass significantly reduces morbidity. We conclude that cardiopulmonary bypass should be avoided whenever possible in reoperative coronary bypass surgery.