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Biomedical subjects

J M Craver

Publications and source records attributed to J M Craver.

At least 55 records · Page 3Linked to original sources
PubMed1990

Aortic valve debridement by ultrasonic surgical aspirator: a word of caution.

Aortic stenosis was relieved in 11 patients by ultrasonic debridement of the valve and annulus, while 102 other patients underwent valve replacement for aortic stenosis during 1988. Debridement was selectively applied based on findings of small annulus size (19 mm or less) and extensive calcification. Additional patient characteristics were mean transvalvular gradient of 78 mm Hg, advanced age, and marked left ventricular hypertrophy. Six patients had no residual gradient and 5 others a mean gradient less than 10 mm Hg. There were no complications related to the debridement process. Intraoperative transesophageal Doppler echocardiography demonstrated improved leaflet mobility and elimination of the gradient in all patients and elimination of associated valvular insufficiency in 2 patients. Follow-up echocardiography demonstrated late onset of new valvular regurgitation in 5 patients that was progressive and required reoperation in 3. Thickened, hardened, and retracted valve leaflets with loss of central coaptation were found in all 3 patients who underwent reoperation. Ultrasonic debridement can effectively relieve aortic stenosis, provide an excellent immediate hemodynamic result, and decrease operative time. However, the early occurrence of aortic insufficiency in a high percentage of patients makes it an unacceptable alternative to valve replacement, and the technique should be abandoned as a treatment for severe calcific aortic stenosis.

Aged↗
PubMed1990

Ten-year experience with the porcine bioprosthetic valve: interrelationship of valve survival and patient survival in 1,050 valve replacements.

The porcine bioprosthetic valve was used in 440 patients having isolated mitral valve replacement (MVR), 522 patients having isolated aortic valve replacement (AVR), and 88 patients having MVR + AVR between 1974 and 1981. Patients with associated surgical procedures were excluded. Mean follow-up was 8.3 years. At 10 years, there was no difference in patient survival between those having AVR and those having MVR. Reoperations were performed on 192 patients. Endocarditis was the reason for reoperation in 3.7% of patients who had MVR and 10.6% of those who had AVR. Structural valve degeneration was the reason for reoperation in 89.7% of MVR patients and 78.8% of AVR patients (p = 0.04). Hospital mortality among patients having valve reoperations was 4.7%. At 10 years, the freedom from valve reoperation for all causes and from structural valve degeneration was significantly better for the AVR group than the MVR group (74% +/- 3% versus 61% +/- 4%, p = 0.004; and 79% +/- 3% versus 63% +/- 4%, p = 0.0006, respectively). For patients in their 60s, the 10-year freedom from reoperation was 92% +/- 2% for AVR and 80% +/- 6% for MVR (p = not significant). At 10 years, freedom from cardiac-related death and valve reoperation was best for both MVR and AVR patients in their 60s. Patients 70 years old or older rarely had reoperation but died before valve failure occurred. The 10-year freedom from all major valve-related events (cardiac-related death, reoperation, thromboembolism, endocarditis, and anticoagulant-related bleeding) was practically the same for both MVR and AVR patients (48% +/- 3% versus 49% +/- 3%, respectively). The porcine bioprosthetic valve is the valve of choice only for patients 60 years old or older. Patients in their 70s have an extremely low rate of reoperation but a high rate of cardiac-related death and do not outlive the prostheses.

Adolescent↗
PubMed1990

Case-matched comparison of mitral valve replacement and repair.

Carpentier's techniques of prosthetic ring mitral valve repair for mitral regurgitation offer the potential for immediate and long-term improvement in valve function without the necessity of replacing the native valve with a prosthesis. A consecutive, case-matched series of 65 patients with prosthetic ring mitral valve repair was compared with 65 patients undergoing mitral valve replacement for mitral regurgitation. The aortic cross-clamp time was 57 +/- 33 minutes in the repair operations and 41 +/- 25 minutes in the replacement operations (p = 0.003). The cardiopulmonary bypass time was 154 +/- 44 minutes in the repair operations and 113 +/- 41 minutes in the replacement operations (p = 0.0001). There were no myocardial infarctions in the hospital in either group. Hospital death was noted in 1.5% of repairs and 4.6% of replacements (p = not significant). Survival at 4 years was 0.84 for repairs and 0.82 for replacements (p = not significant). Freedom from reoperation to replace the mitral valve at 4 years was 62 of 65 patients in the repair group and 64 of 65 patients in the replacement group (p = not significant). In-hospital and midterm results in a closely matched population show that mitral valve repair yields results comparable with those of replacement despite a more difficult procedure. The benefits of maintaining the native valve with chordal and papillary muscle structure intact and avoidance of prosthetic valve implantation may then become apparent with longer follow-up.

Adult↗
PubMed1990

Results of coronary surgery after failed elective coronary angioplasty in patients with prior coronary surgery.

The results of coronary artery bypass surgery after failed elective coronary angioplasty in patients who have undergone prior coronary surgery are unknown. Coronary angioplasty may be performed to relieve angina after surgery either to the native coronary vessels or to grafts. Failure of attempted coronary angioplasty may mandate repeat coronary surgery, often in the setting of acute ischemia. From 1980 to 1989, 1,263 patients with prior coronary bypass surgery underwent angioplasty; of these patients, 46 (3.6%) underwent reoperation for failed angioplasty during the same hospital stay. Of the 46 patients who underwent reoperation, 33 had and 13 did not have acute ischemia. In the group with ischemia, 3 patients (9.1%) died and 14 (42.4%) died or had a Q wave myocardial infarction in the hospital compared with no deaths (p = NS) and no deaths or Q wave myocardial infarction (p = 0.005) in the group without ischemia. At 3 years, the actuarial survival rate was 88 +/- 6% in the group with ischemia, whereas there were no deaths in the group without ischemia (p = NS), and freedom from death or myocardial infarction was 51 +/- 10% in the group with ischemia, versus no events in the group without ischemia (p = 0.006). In most patients with prior coronary bypass surgery, coronary angioplasty was performed without the need for repeat coronary bypass surgery. Should coronary angioplasty fail, reoperation in patients without acute ischemia can be performed with overall patient survival comparable to that of elective reoperative coronary bypass without coronary angioplasty.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1990

Failed elective percutaneous transluminal coronary angioplasty requiring coronary artery bypass surgery. In-hospital and late clinical outcome at 5 years.

This study was performed to define the in-hospital and late clinical outcome at 5 years in 430 patients who had a failed elective percutaneous transluminal coronary angioplasty (PTCA) and underwent coronary artery bypass graft (CABG) surgery during their hospitalization. This group comprised 5.9% of 7,246 patients undergoing elective PTCA. CABG surgery was performed in 346 patients with ongoing myocardial ischemia (80.5%) and in 84 patients without ischemia (19.5%). Their mean age was 56 +/- 9 years, and 76.3% were male. One-vessel disease was present in 72.3%, and the mean left ventricular ejection fraction was 59 +/- 11%. Overall, 1.9 +/- 0.9 bypass grafts were placed. There was increased use of the internal thoracic artery in the nonischemic group. A new nonfatal postprocedural Q wave myocardial infarction occurred in 21.2% and occurred more frequently in the ischemic (25.4%) than in the nonischemic (3.6%) group (p less than 0.0001). There were six in-hospital deaths (1.4%), an incidence that did not differ between the two groups. Follow-up was 99.8% complete. There were 25 deaths (93.2 +/- 1.5%, 5-year survival), including 16 of cardiac cause (95.3 +/- 1.3%, 5-year cardiac survival). Q wave myocardial infarction occurred in 111 patients (91 in-hospital), and freedom from cardiac death or nonfatal myocardial infarction at 5 years was 71 +/- 3%. In the group going to CABG surgery with ongoing ischemia, the 5-year cardiac survival was 94.9 +/- 1.6%, and in the group without ischemia, the corresponding survival was 96.2 +/- 2.2%. By multivariate analysis, the presence of preoperative myocardial ischemia, pre-PTCA diameter stenosis less than 90%, and the presence of multiple-vessel disease correlated with the occurrence of cardiac death or nonfatal myocardial infarction at 5 years. At this large-volume center with extensive PTCA operator and surgical experience, the excellent survival and low event rates over 5 years support the concept that despite the failed elective PTCA procedure, there was little effect on long-term survival provided the patient underwent prompt successful surgical revascularization.

Aged↗
PubMed1988

Left atrial tumor embolization during pulmonary resection: review of literature and report of two cases.

In the past 10 years, 2 patients were seen with metastatic sarcoma to the lower lobe of the lung and extension into the left atrium. In both patients, an attempt to squeeze the intracardiac portion of the tumor into the lung at the time of lobectomy ended in near-catastrophic complications: In the first patient, a saddle embolus occluded both femoral arteries, and in the other, obstruction of the mitral valve orifice and cardiac arrest occurred. This approach is mentioned only to condemn it. Our recommended approach is outlined to prevent this technical mistake in the future.

Adult↗
PubMed1988

Trends in invasive treatment of single-vessel and double-vessel coronary disease.

We examined our practice of invasive therapy for one- and two-vessel coronary disease to assess the impact of the randomized trials of coronary surgery and the current use of angioplasty. We first reviewed our results with coronary artery bypass graft in equivalent patients in the Coronary Artery Surgery Study with one- and two-vessel disease between 1976 and 1981. Among 1376 patients, hospital mortality was 0.07%, and 5-year survival was 95.2% +/- 0.8%. To define trends in invasive therapy, which have since occurred, we compared 100 patients with one- and two-vessel disease in each of three groups: 1979 coronary artery bypass graft, 1984 coronary artery bypass graft, and 1984 percutaneous transluminal coronary angioplasty. Preoperative characteristics in the average 1979 and 1984 patients were similar; however, in 1984, patients who had a coronary artery bypass graft were older than patients who had percutaneous transluminal coronary angioplasty (61.5 versus 56.7 years, p less than 0.01), they required more heart medications (2.1 versus 1.5, p less than 0.01), had more previous infarctions (0.8 versus 0.5, p less than 0.01), and more patients had an ejection fraction of less than 50% (34% versus 7%, p less than 0.01). Patients who had angioplasty had a shorter postoperative stay (median number of days 7, 7, 2, p less than 0.01). Freedom from major complications was similar among the groups (91%, 87%, 85%). Unstable symptoms were the most frequent indication for invasive therapy (approximately 80%), whereas long-term symptoms, those considered in the randomized trials, occurred in relatively few patients. The number of patients without at least one definite indication for invasive therapy was 13%, 3%, and 11%, p less than 0.05, suggesting that the indications for the 1984 coronary artery bypass graft group have become more restrictive since the 1979 coronary artery bypass graft group. Indications for the 1984 percutaneous transluminal coronary angioplasty group remained less restrictive, being similar to those for the 1979 coronary artery bypass graft group. A continuing trend toward the use of percutaneous transluminal coronary angioplasty was evident, as 56% of the 1979 coronary artery bypass graft group of patients and 32% of the 1984 coronary bypass group of patients would be offered percutaneous transluminal coronary angioplasty rather than coronary artery bypass graft on the basis of 1986 percutaneous transluminal coronary angioplasty criteria. The p values were obtained with analysis of variance or chi 2 test.

Angioplasty, Balloon↗
PubMed1988

Treatment of moderate mitral regurgitation and coronary disease by coronary bypass alone.

We have favored treatment of moderate mitral regurgitation and coronary disease with coronary bypass alone because of the high operative mortality of combined mitral valve replacement and coronary bypass. Between 1977 and 1983, coronary bypass alone was performed on 58 patients (mean age 63 +/- 8 years). Preoperatively, 90% had Canadian Cardiovascular Society class III or IV angina, and 10% had class III or IV congestive heart failure. In 72% mitral regurgitation had been caused by coronary disease. Hospital mortality was 3.4% (2/58). At follow-up (100% complete, mean 4.3 years) 66% of survivors were functional classes I and II (compared with 7% preoperatively, p less than 0.0001). Of those patients who worked preoperatively, 84% returned to work. There were no reoperations. The 5-year survival was 77%. In the same period combined mitral valve replacement and coronary bypass was required in 20 unmatched patients with moderate mitral regurgitation and coronary disease. Indications for valve replacement included congestive heart failure (10 cases), high left atrial pressure (three cases), and mitral stenosis (four cases). In these patients with more advanced symptoms the hospital mortality was 25%, and the 5-year survival was 31%. Treatment of moderate mitral regurgitation and coronary disease by coronary bypass alone achieved excellent hospital survival and long-term functional stability without a subsequent valve operation.

Aged↗
PubMed1988

Predictors of mortality, complications, and length of stay in aortic valve replacement for aortic stenosis.

The introduction of aortic balloon valvuloplasty has prompted review of established techniques to treat aortic valve disease. To this end, the surgical results were reviewed for 1,148 patients undergoing aortic valve replacement, with and without associated coronary artery bypass grafting, for aortic stenosis between January 1, 1975 and September 1, 1987. The overall death rate was 4.6%. The neurological event rate (stroke or reversible ischemic event) was 4.2%, the myocardial infarction rate was 3.5%, and 30.7% had a hospital stay in excess of 10 days. Mortality for isolated elective aortic valve replacement rose from 2.5% for patients under age 70 to 7.3% for those over age 70. Mortality for elective aortic valve replacement plus coronary bypass was 3.8% for patients under age 70 and 11.6% for patients over age 70. The neurological event rate rose from 3.0% to 8.4% and the prolonged length of stay from 28% to 42%. By stepwise logistic regression analysis, the predictors of in-hospital mortality were age and emergent surgery. Age was the only multivariate predictor of neurological events. The year of surgery and emergent status were the multivariate predictors of prolonged length of hospital stay. Aortic valve replacement for aortic stenosis is a well-established technique with low neurological event rates and mortality, which may be predicted in advance. Newer techniques must be considered in light of data such as these.

Aged↗
PubMed1986

Reoperation for prosthetic valve degeneration after Konno aortoventriculoplasty.

Since the introduction of the aortoventriculoplasty procedure by Konno in 1975, 16 patients have undergone aortic root augmentation by this method at the Woodruff Medical Center of Emory University. In four patients bioprosthetic valve degeneration 2 to 5 years after the Konno procedure has necessitated repeat operation and replacement of the prosthetic aortic valve. Modification of the septal patch or repeat right ventriculotomy has not been required. One patient required an additional lateral anulus-enlargement procedure (Manouguian) whereas the other three have demonstrated stability or growth of the aortic anulus. We have not observed recurrent subvalvular stenosis or problems with the right ventricular outflow tract. Repeat operation after aortoventriculoplasty has been relatively simple and has usually involved only the supra-annular aorta.

Adult↗
PubMed1985

Ruptured papillary muscle, a complication of myocardial infarction: clinical presentation, diagnosis, and treatment.

Ruptured papillary muscle due to myocardial infarction was encountered in 14 patients during the period 1975-1983. Five of the 14 patients had a history of angina pectoris and two had a history of prior myocardial infarction. Eleven patients with myocardial infarction developed additional pain due to myocardial ischemia and/or a murmur of mitral regurgitation and pulmonary edema within a week, 3 others had a prolonged course with intermittent pain due to myocardial ischemia and breathlessness for longer periods and then deteriorated. Thirteen of our 14 patients developed a murmur and all but one had pulmonary edema on the chest x-ray. Five patients had infarction patterns on the electrocardiogram, the remainder of the patients had only ST- and T-wave changes. Echocardiograms showed fine flutter and notching of the anterior mitral leaflets and vigorous contractions of the left ventricle. Only one patient was demonstrated to have a papillary muscle tip prolapsing into the left atrium on two-dimensional echocardiography. Twelve patients underwent surgery and 8 survived. Seven patients had single-vessel coronary disease, 4 involving the circumflex system and 3 involving the right coronary system. Four of the 7 patients with single-vessel coronary disease survived surgery. Five patients went to surgery with the intra-aortic balloon pump in place and only 3 survived. Three others had the pump inserted intraoperatively and 2 of these survived. Six of 9 patients who had mitral valve replacement and coronary bypass survived. Ejection fraction ranged from 40 to 79%. Surgical survival did seem to be related to the extent of papillary muscle rupture, with the best results occurring in the group with a small portion of the tip ruptured. Seven patients had a stormy clinical course and required surgery within 10 days of rupture. Four of these 7 survived. It seems reasonable to believe that these patients who often have small infarction and limited coronary disease have good potential for survival. Our approach has been to move toward surgery once the diagnosis is made to avoid the sudden deterioration that frequently occurs. The surgical mortality in this group remains in the 30 to 40% range.

Aged↗
PubMed1985

Avoidance of transverse midventricular disruption following mitral valve replacement.

From 1974 through 1977 when our hospital mortality for aortic valve replacement and myocardial revascularization was 3.5% and 1.1%, respectively, hospital mortality for mitral valve replacement (MVR) was 8.3% (13/156)--as high as 14.9% in 1976. Transverse midventricular disruption (TMD) was present in 7 of 10 patients on whom an autopsy was done and was clinically diagnosed in 3 others without postmortem examination. Transverse midventricular disruption presented as refractory myocardial failure immediately on termination of bypass or later (1 to 5 days) after an initial period of good hemodynamics. It appeared to result when volume loading or afterload pressure was returned to the untethered ventricle after MVR performed with potassium-induced, cold cardioplegia and ischemic arrest. Operative techniques were modified to preserve a portion of the mitral suspensory mechanism, to extend the reperfusion interval following cardioplegia and ischemic arrest, and to control strictly ventricular volume and pressure loading following bypass. By utilizing these methods, TMD was avoided from 1978 through 1982, and hospital mortality for MVR was 3.7% (9/241). The improved hospital mortality and avoidance of TMD did not result from patient selection. Allowing adequate time for recovery of the myocardium after cardioplegia plus ischemic arrest prior to ventricular loading, preservation of mitral suspensory function, and strict control of preload and afterload pressures have been effective in lowering hospital mortality for MVR and have eliminated TMD in a 5-year period.

Aged↗
PubMed1985

Effect of enflurane, isoflurane, and halothane on pacing stimulation thresholds in man.

Volatile anesthetic agents are often used in patients who require temporary epicardial pacing after cardiopulmonary bypass (CPB). However, the effect of anesthetic agents on energy stimulation thresholds is unknown. After CPB, 24 patients under diazepam-narcotic-pancuronium anesthesia ventilated with an FIO2 = 1.0 received equipotent concentrations of either enflurane, isoflurane, or halothane. Using temporary epicardial electrodes, energy stimulation thresholds were calculated using the data derived from a pacing systems analyzer. Volatile anesthetics do not change energy stimulation thresholds from those already present under diazepam-narcotic-pancuronium anesthesia.

Cardiac Pacing, Artificial↗
PubMed1985

Improved myocardial recovery after cardioplegic arrest with an oxygenated crystalloid solution.

Possible enhancement of myocardial protection by oxygenation of a crystalloid cardioplegic solution was evaluated in a three-part study. In Part I, canine hearts underwent ischemia followed by heterogeneous cardioplegic arrest for 45 to 60 minutes. Oxygenation led to improved recovery in the left anterior descending region (47% versus 86% recovery, p less than 0.05) (15 minutes of ischemia) and in the circumflex region (9.5% versus 52% recovery, p less than 0.05) (30 minutes of ischemia). Part II was a blind prospective randomized study in 12 patients. It examined creatine kinase, myoglobin, and lactate as well as coronary sinus flow, oxygen consumption, and cardiac work 1 hour after aortic cross-clamping during atrial and during ventricular pacing. No significant difference was demonstrable between control and oxygenated solutions. In Part III, 57 coronary bypass patients were protected with a nonoxygenated solution while 94 patients received an identical oxygenated solution. Twelve-hour creatine kinase levels were similar in the nonoxygenated (9.5 +/- 16 IU, +/- standard deviation) and oxygenated (11 +/- 22 IU) groups if the cross-clamp interval was 28 minutes or less. In patients subjected to longer than 28 minutes of arrest, the 12 hour creatine kinase MB levels were more than twice as high in the nonoxygenated group (26.5 +/- 26 IU) compared to the oxygenated group (9.9 +/- 14 IU, p less than 0.05). In this canine model of heterogeneous cardioplegia and in the routine conduct of coronary bypass operations, oxygenated crystalloid cardioplegia is superior to an identical nonoxygenated solution.

Animals↗
PubMed1985

Mediastinitis after cardiac valve operations. Impact upon survival.

Mediastinitis after cardiac valve replacement is a dreaded complication with consequent mortality estimated as high as 70%. We have reviewed 2,491 patients with cardiac valve operations to assess the impact of mediastinitis upon mortality in our institution in the past 10 years. Mediastinitis developed after valve replacement in 36 patients (1.4%). All patients required operative intervention for mediastinal infection with positive bacterial cultures. Twelve of these patients had other perioperative problems associated with a high mortality independent of mediastinitis: bacterial endocarditis not cured by valve replacement (three), recent preoperative myocardial infarction (four), triple valve disease with biventricular failure (one), and severe perioperative cerebral damage (four). Ten of these high-risk patients died (83.3%). The impact of mediastinitis upon survival is best evaluated in the remaining 24 patients without high-risk perioperative problems. Eight of these patients were managed before 1980 with débridement and irrigation as the primary treatment, with two hospital deaths (25%). Pectoral or rectus muscle flaps were frequently used after 1980 (flaps in 11 of 16 patients), leading to a significantly shorter time between diagnosis of infection and hospital discharge free of infection (62 versus 385 days, p less than 0.05). Only one of these 16 patients died. Valve re-replacement for endocarditis was performed in three of these 24 patients although 13 of 24 had positive blood cultures. Mediastinitis after valve operations in the absence of other high-risk perioperative problems can be successfully managed. Early débridement and muscle flap closure has led to a 94% survival rate in 16 patients during the past 4 years.

Adult↗
PubMed1984

Comparison of coronary artery bypass surgery and percutaneous transluminal coronary angioplasty including surgery for failed angioplasty.

Selection and treatment of patients with ischemic heart disease is presently undergoing an evolutionary trend. Percutaneous transluminal coronary angioplasty (PTCA) has been recommended as the initial procedure for many patients with coronary artery disease and has thus redefined candidates for coronary artery bypass surgery. During our first years of experience with percutaneous angioplasty, 339 patients underwent the procedure and were compared with 338 patients who underwent isolated coronary artery bypass surgery. Patients who underwent PTCA had a shorter duration of angina and a lower number of prior myocardial infarctions and were found to have better left ventricular function (p less than 0.01). PTCA was considered initially successful in 87% (295 of 339) of patients. The most common finding at operation in those with failed angioplasty who underwent urgent or emergency revascularization was dissection of atheromatous plaque. Although the cumulative frequency of new Q waves in the entire 18-month angioplasty series was low (2.7%), the incidence was high (18%) in those with angioplasty failure and subsequent operation (N = 20) and significantly greater than in patients who had elective coronary artery bypass surgery (3.6%). Use of inotropic agents and lidocaine for ventricular arrhythmias was significantly higher in patients with unsuccessful PTCA who required operation than in those who underwent elective bypass surgery (10% vs 3% and 10% vs 1.5%, respectively; p less than 0.01). In an analysis of our entire experience between October 1980 and June 1982, 777 patients who had PTCA and 2068 patients who underwent coronary artery bypass surgery were analyzed for differences in clinical complications and early outcome.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1984

Distal coronary artery dissection following percutaneous transluminal coronary angioplasty.

The most common cause of acute myocardial ischemia following percutaneous transluminal coronary angioplasty is coronary dissection, which characteristically remains localized to the site of balloon dilation. In this article, however, we report on 4 patients in whom percutaneous transluminal coronary angioplasty was complicated by coronary artery dissection extending distally beyond the site of anticipated vein graft anastomosis. Intraoperative diagnosis of distal coronary dissection is suggested by a characteristic appearance of the artery and confirmed by the finding of true and false lumens at the time of coronary arteriotomy. Successful revascularization is achieved by anastomosis of a vein graft to the true lumen with reapproximation of the dissected arterial layers. Proximal coronary artery ligation in this setting is unnecessary.

Adult↗