Dan Lindblom

Postoperative stroke in cardiac surgery is related to the location and extent of atherosclerotic disease in the ascending aorta

OBJECTIVES The aim of the study was to evaluate the risk from calcified atheromas in the ascending aorta, and the extent and topography of the disease in the development of stroke after cardiac surgery. BACKGROUND Postoperative stroke constitutes a serious problem in cardiac surgery, and atherosclerosis of the ascending aorta is an important risk factor. METHODS Before surgical manipulation epiaortic echocardiographic ultrasound was performed to evaluate the ascending aorta in 921 consecutive patients undergoing cardiac surgery. The presence of calcification, location of atheroma, extent of the disease and clinical variables including postoperative stroke were recorded prospectively. RESULTS A total of 26.2% of the patients had atherosclerosis of the ascending aorta, and in 44.4% of them more than one of 12 possible segments was involved. Logistic regression showed that atherosclerotic disease in the ascending aorta was the most important predictive factor for postoperative stroke. The incidence of stroke was 1.8% in patients without atherosclerotic disease of the ascending aorta, and 8.7% in patients with the disease (p < 0.0001). Diabetes mellitus was also a predictive factor (p = 0.04). A new and unique finding of this study was that the middle-lateral segment is an independent predictive factor for postoperative stroke, with a relative risk of 26% (p = 0.04). CONCLUSIONS Patients with atheromatosis in the ascending aorta had an 8.7% incidence of postoperative stroke, in spite of minor surgical modifications. The risk depended on the presence, location and extent of the disease. Randomized trials evaluating alternative surgical strategies in coronary surgery are urgently needed in high risk patients.

Pre-operative mild cognitive dysfunction predicts risk for post-operative delirium after elective cardiac surgery.

Background and Aims: To identify pre-operative risk factors for delirium in patients undergoing elective cardiac surgery, using clearly defined diagnostic criteria for delirium, and a thorough clinical assessment. Methods: The incidence of post-operative delirium in 107 patients ≥60 years undergoing elective cardiac surgery was calculated. None of the patients included suffered from dementia. Pre-operative cognitive function in all patients was assessed using the Mini Mental State Examination (MMSE) and post-operative delirium was diagnosed using the Confusion Assessment Method (CAM). Post-operative clinical and cognitive assessments were carried out for all patients. Results: Twenty-five patients (23.4%) developed delirium post-operatively. Clinical parameters, including age, gender, co-morbidities, medications, and peri-operative parameters, were similar in patients with and without post-operative delirium. Patients with pre-operative subjective memory complaints and lower MMSE scores, undergoing valve operation or valve + coronary artery bypass grafting (CABG), exhibited an increased risk of developing post-operative delirium. Additionally, delirious patients had a significant decline in post-operative MMSE score compared with the non-delirious ones. Conclusions: The main pre-operative risk factors for post-operative delirium after elective cardiac operations were subjective memory complaints, mild cognitive impairment, and type of cardiac surgery, such as valve procedures. This study suggests that cognitive evaluation should be included in pre-operative assessment.

Effects of intramyocardial injection of phVEGF‐A165 as sole therapy in patients with refractory coronary artery disease – 12‐month follow‐up: Angiogenic gene therapy

Abstract. Sarkar N, Rück A, Källner G, Y‐Hassan S, Blomberg P, Islam KB, van der Linden J, Lindblom D, Nygren AT, Lind B, Brodin L‐Å, Drvota V, Sylvén C (Karolinska Institute, Huddinge University Hospital, Novum, Stockholm, Sweden). Effects of intramyocardial injection of phVEGF‐A165 as sole therapy in patients with refractory coronary artery disease: 12‐month follow‐up. Angiogenic gene therapy. J Intern Med 2001; 250: 373–381.

HLA-B27: An important genetic risk factor for lone aortic regurgitation and severe conduction system abnormalities

PURPOSE HLA-B27, an immunogenetic marker that is present in 8 percent of the white population around the world, has been found to be an important risk factor for the development of a group of rheumatic disorders, the seronegative spondyloarthropathies. Our objective was to assess the possible role of HLA-B27 and the associated inflammatory disease process in the development of lone aortic regurgitation. PATIENTS AND METHODS A group of 91 patients with lone aortic regurgitation were studied by HLA typing and clinical and roentgenologic examination. RESULTS The HLA-B27-associated inflammatory disease process was found to be the probable underlying cause in 15 to 20 percent of patients with lone aortic regurgitation of different degrees of severity. Furthermore, HLA-B27 was found in 88 percent of the male patients with the combination of aortic regurgitation and severe conduction system abnormalities. CONCLUSION We suggest that this cardiac syndrome should be regarded as an HLA-B27-associated syndrome, sometimes part of ankylosing spondylitis or Reiters disease, but just as often presenting without obvious rheumatic disease. The marker is thus an important and widely distributed risk factor not only for the development of rheumatic disease but also for acquired aortic regurgitation and sever conduction system abnormalities.

Aortic valve replacement in octogenarians with aortic stenosis: A case-control study☆

OBJECTIVES This study was designed to compare the results of aortic valve replacement in patients greater than or equal to 80 years old with those in patients 65 to 75 years old. BACKGROUND Aortic valve replacement may be potentially more complicated and require the use of more resources when performed in octogenarians rather than in younger patients. Few hard data on this possibility are available. METHODS The study group comprises all 44 patients greater than or equal to 80 years old (mean age 82 years) who underwent aortic valve replacement at our institution between January 1981 and July 1989. A control group of 83 patients with a mean age of 70 years was matched with the study group for gender and approximate date of valve replacement. Before operation, 86% of the older patients versus 36% of the younger patients were in New York Heart Association functional class III or IV (p less than 0.001). Data were retrospectively collected from hospital records and a self-assessment telephone interview was conducted. RESULTS The early mortality rate was 14% in the older group versus 4% in the younger group (p = 0.045). The duration of respirator support, intensive care and the total duration of the hospital stay did not differ significantly between groups. The incidence of postoperative low cardiac output syndrome was higher in the older group (p = 0.049), but the incidence of late valve-related complications was similar in the two groups. The 2-year survival rate (including data on patients who died early) was 73% in the older group and 90% in the younger group (p = NS). Six months postoperatively all patients but one were in functional class I or II. CONCLUSIONS Although the patients greater than or equal to 80 years old had a poorer preoperative status than that of younger patients, aortic valve replacement in this group did not require more use of hospital resources and resulted in a clinical improvement comparable to that of younger patients.

MANAGEMENT OF DEEP STERNAL WOUND INFECTION AFTER CARDIAC SURGERY-HANUMAN SYNDROME

Deep sternal wound infection following open-heart surgery caused sternal osteitis in eight patients and mediastinitis in 27 during 1980-1989. The incidence of such infection was 0.5%. Infection was more common during the last 2 years than in 1980-1987 (0.8% vs. 0.4%), and when bilateral internal mammary artery grafts were dissected (3.2% vs. 0.6% when only one internal mammary artery was used). Cure of mediastinitis was achieved by primary closed irrigation in four of 13 patients and by primary open treatment in five of ten. Muscle flap was employed in totally ten patients and omentum in four before final elimination of infection. Of the 27 patients with mediastinitis, eight (30%) died in the post-operative period of cardiac failure (3 cases), disseminated infection (2), bleeding (2) or aspiration (1). The 5-year survival rate was 43%. Prosthetic value endocarditis caused one late death and necessitated one reoperation. If eradication of postoperative mediastinitis is not achieved by early diagnosis, debridement and closed irrigation, transposition of muscle or omentum should be considered.

16S rDNA sequencing of valve tissue improves microbiological diagnosis in surgically treated patients with infective endocarditis

OBJECTIVES The aim was to evaluate 16S rDNA sequencing in heart valves in patients with infective endocarditis undergoing surgery. METHODS Fifty-seven patients with infective endocarditis were examined in this prospective study by analysing heart valves with 16S rDNA sequencing and culturing methods and comparing the results to blood cultures. As controls, heart valves from 61 patients without any signs of endocarditis were examined. RESULTS All together 77% of the endocarditis patients were positive for 16S rDNA, 84% had positive blood cultures and 23% had positive cultures from heart valves, whereas only 16% of the cultures from heart valves were concordant with results from blood cultures or 16S rDNA. Concordant results between 16S rDNA sequencing and blood cultures were found in 75% patients. All controls were negative for 16S rDNA. In 4 out of 9 patients with negative blood cultures, the aetiology was established by 16S rDNA alone, i.e. viridans group streptococci. CONCLUSION In this Swedish study, 16S rDNA sequencing of valve material was shown to be a valuable addition in blood culture-negative cases. The value of heart valve culture was low. Molecular diagnosis using 16S rDNA sequencing should be recommended in patients undergoing valve replacement for infective endocarditis.

The monostrut Björk-Shiley heart valve

To avoid the possibility of a fracture of the welded two-armed outflow strut of the Björk-Shiley heart valve, since 1982 it has been machined from one piece of Haynes 25 in the form of a monostrut valve without welds. Of the first 864 patients with a monostrut Björk-Shiley valve implanted, 268 have now been followed up to 3 years. The clinical findings, as well as absence of hemolysis, excellent hemodynamics even with a narrow aortic root as demonstrated by transseptal cardiac catheterization and excellent functional improvement are reported. No valve thrombosis in patients receiving anticoagulant therapy was observed with valves in either the aortic or the mitral position and there was no case of mechanical failure.

Myocardial release of troponin T after coronary bypass surgery

The temporal changes in cardiac S-troponin T, S-creatine kinase-MB(S-CK-MB)mass and S-myoglobin were studied for 5 days after coronary bypass grafting in 70 patients. Perioperative infarction occurred in ten patients (2 Q wave, 8 non-Q wave). All three markers showed significant increase even in patients without signs of perioperative infarction. Within 8-12 hours their levels rose significantly (p < 0.001) more in the infarction than in the non-infarction cases. Troponin T and CK-MBmass both showed early (< 8-12 h) peaks in patients with perioperative infarction. CK-MBmass returned to near normal levels within 48-72 hours, whereas troponin T remained markedly increased throughout the observation. Myoglobin concentrations varied widely among the infarction cases. In the non-infarction group, troponin T and CK-MBmass (but not myoglobin) were related to the aortic cross-clamp time. Troponin T (but not CK-MBmass) remained elevated throughout the study period in patients with longer cross-clamp times. These findings may indicate continuous release from damaged myocardium in cases of perioperative infarction. Troponin T and CK-MBmass can serve as markers of perioperative infarction and troponin T may also be useful as a marker in studies on myocardial protection.

Survival and Quality of Life in Cardiac Surgery Patients With Prolonged Intensive Care

BACKGROUND The clinical outcome in discharged cardiac surgery patients after prolonged postoperative intensive care needs further investigation. The aim was to study survival, functional status, and quality of life in cardiac surgery patients with more than 10 days postoperative intensive care unit stay. METHODS We performed a population-based study including 4,086 cardiac surgery patients and identified 141 patients who had a postoperative intensive care unit stay of more than 10 days. Data regarding patients and outcome were collected, and all discharged patients alive in May 2008, or a family member, were contacted to assemble information regarding functional status and quality of life using the Karnofsky performance scale and the Short Form-36 questionnaire. RESULTS Early mortality was 33%. Risk factors for early mortality were advanced age and postoperative dialysis. Survival at 1, 3, and 5 years was 62%, 56%, and 52%, respectively. Ninety-five patients were discharged from the hospital, and during a mean follow-up of 1.9 years, 62% were readmitted at least once. In discharged patients, 65% had a Karnofsky score of 80 or more. We found significantly lower physical (39.7 versus 43.6; p = 0.03), and mental (44.1 versus 50.8; p = 0.001) scores in the study group compared with a reference group. CONCLUSIONS Early mortality was high, especially in patients who required dialysis. However, long-term survival and functional status were encouraging. Quality of life was worse compared with the general population in both physical and mental aspects, but the difference was moderate. Extensive efforts in this patient group seem reasonable despite high resource utilization.