Torbjörn Ivert

The Swedish Web-system for Enhancement and Development of Evidence-based care in Heart disease Evaluated According to Recommended Therapies (SWEDEHEART)

Aims The aims of the Swedish Web-system for Enhancement and Development of Evidence-based care in Heart disease Evaluated According to Recommended Therapies (SWEDEHEART) are to support the improvement of care and evidence-based development of therapy of coronary artery disease (CAD). Interventions To provide users with online interactive reports monitoring the processes of care and outcomes and allowing direct comparisons over time and with other hospitals. National, regional and county-based reports are publicly presented on a yearly basis. Setting Every hospital (n=74) in Sweden providing the relevant services participates. Launched in 2009 after merging four national registries on CAD. Population Consecutive acute coronary syndrome (ACS) patients, and patients undergoing coronary angiography/angioplasty or heart surgery. Includes approximately 80 000 new cases each year. Startpoints On admission in ACS patients, at coronary angiography in patients with stable CAD. Baseline data 106 variables for patients with ACS, another 75 variables regarding secondary prevention after 12–14 months, 150 variables for patients undergoing coronary angiography/angioplasty, 100 variables for patients undergoing heart surgery. Data capture Web-based registry with all data registered online directly by the caregiver. Data quality A monitor visits approximately 20 hospitals each year. In 2007, there was a 96% agreement. Endpoints and linkages to other data Merged with the National Cause of Death Register, including information about vital status of all Swedish citizens, the National Patient Registry, containing diagnoses at discharge for all hospital stays in Sweden and the National Registry of Drug prescriptions recording all drug prescriptions in Sweden. Access to data Available for research by application to the SWEDEHEART steering group.

Cardiac Myxoma: 40 Years’ Experience in 63 Patients

BACKGROUND Cardiac myxomas were resected in 63 patients, including the first successful procedure in the world. METHODS Patient data and data obtained during follow-up of the survivors were reviewed. RESULTS Preoperatively, valve obstruction occurred in 56% and emboli in 32% of the patients. The myxomas were located in the left atrium in 88%, right atrium in 10%, and both atria in 1 patient (1.6%). One patient died early, and 5 died late. The 20-year survival rate was 85%. At a median of 13 years (range, 1 month to 42 years) after resection, 26% of the survivors reported having various cardiopulmonary symptoms, 5% had had thromboembolic events, and 69% were asymptomatic. After 2 years, there was a recurrence in a young woman who had had a multifocal myxoma at the time of the primary operation. No other evidence of recurrence was found at autopsy or during repeat echocardiography in the remaining patients during an observation period of 787 patient-years. CONCLUSIONS Surgical resection of a single myxoma is a safe and effective treatment, with a low risk of recurrence. After uncomplicated resection, the frequency with which postoperative echocardiography is performed should be limited.

Obesity and the risk of early and late mortality after coronary artery bypass graft surgery

BACKGROUND Obesity is often considered to be a significant risk factor for postoperative mortality when selecting candidates for coronary artery bypass grafting (CABG). METHODS We included all patients undergoing a first isolated CABG at the Karolinska Hospital in Stockholm, Sweden, between 1980 and 1995 (n = 6728). Patients were categorized on the basis of body mass index (BMI): non-overweight (BMI <25 kg/m2), overweight (25 kg/m2 < or = BMI <30 kg/m2), and obese (BMI > or =30 kg/m2). Multivariate Cox regression was used to assess the risk of re-operation for bleeding, deep sternal wound infection, and early (< or =30 days) and late (< or =5 years) mortality rates. RESULTS The average length of follow-up was 6.5 years. There were 252 re-operations for bleeding, 53 deep sternal wound infections, and 628 deaths. Patients who were obese had a significantly lower risk of re-operation for bleeding (risk ratio [RR], 0.32; 95% CI, 0.19-0.53), but a greater risk of deep sternal wound infection (RR, 2.66; 95% CI, 1.21-5.88) compared with patients who were not overweight. However, patients who were obese and patients who were not overweight experienced similar 30-day (RR, 0.65; 95% CI, 0.34-1.27), 1-year (RR, 0.56; 95% CI, 0.29-1.10), and 5-year mortality rates (RR, 0.91; 95% CI, 0.66-1.25). Results for patients who were overweight were consistent with those of patients who were obese. CONCLUSION Patients who are obese are not at a greater risk of early and late mortality after CABG compared with patients who are not overweight, although they appear to have a lower risk of re-operation for bleeding and a greater risk of deep sternal wound infection. Therefore, obesity per se is not a contraindication for CABG.

Multi-organ expression profiling uncovers a gene module in coronary artery disease involving transendothelial migration of leukocytes and LIM domain binding 2: the Stockholm Atherosclerosis Gene Expression (STAGE) study.

Environmental exposures filtered through the genetic make-up of each individual alter the transcriptional repertoire in organs central to metabolic homeostasis, thereby affecting arterial lipid accumulation, inflammation, and the development of coronary artery disease (CAD). The primary aim of the Stockholm Atherosclerosis Gene Expression (STAGE) study was to determine whether there are functionally associated genes (rather than individual genes) important for CAD development. To this end, two-way clustering was used on 278 transcriptional profiles of liver, skeletal muscle, and visceral fat (n = 66/tissue) and atherosclerotic and unaffected arterial wall (n = 40/tissue) isolated from CAD patients during coronary artery bypass surgery. The first step, across all mRNA signals (n = 15,042/12,621 RefSeqs/genes) in each tissue, resulted in a total of 60 tissue clusters (n = 3958 genes). In the second step (performed within tissue clusters), one atherosclerotic lesion (n = 49/48) and one visceral fat (n = 59) cluster segregated the patients into two groups that differed in the extent of coronary stenosis (P = 0.008 and P = 0.00015). The associations of these clusters with coronary atherosclerosis were validated by analyzing carotid atherosclerosis expression profiles. Remarkably, in one cluster (n = 55/54) relating to carotid stenosis (P = 0.04), 27 genes in the two clusters relating to coronary stenosis were confirmed (n = 16/17, P<10−27and−30). Genes in the transendothelial migration of leukocytes (TEML) pathway were overrepresented in all three clusters, referred to as the atherosclerosis module (A-module). In a second validation step, using three independent cohorts, the A-module was found to be genetically enriched with CAD risk by 1.8-fold (P<0.004). The transcription co-factor LIM domain binding 2 (LDB2) was identified as a potential high-hierarchy regulator of the A-module, a notion supported by subnetwork analysis, by cellular and lesion expression of LDB2, and by the expression of 13 TEML genes in Ldb2–deficient arterial wall. Thus, the A-module appears to be important for atherosclerosis development and, together with LDB2, merits further attention in CAD research.

Reoperations for bleeding after coronary artery bypass procedures during 25 years

OBJECTIVES AND METHODS To study the incidence, causes and risk factors of reoperation for bleeding, 8563 coronary artery bypass procedures performed during 1970-1994 were reviewed. RESULTS Patients operated on during 1990-1994 were older, the internal mammary artery was used more frequently, more grafts were inserted, more combined and redo bypass procedures were performed than during 1970-1989. There were 402 early resternotomies but in 24 patients (6%) no bleeding was encountered and the compromised haemodynamics was caused by left ventricular failure. Postoperative bleeding caused reoperation in 378 patients (4.4%). There were 3.2% reoperations in 1994. The internal mammary artery or its bed was the main cause of the bleeding in 43%. The reoperations were performed earlier and emergent reoperations because of cardiac tamponade were less common during 1990-1994 than during 1970-1989. Reoperation for bleeding was required in 8.6% of patients 80 years of age and older. Combined coronary bypass surgery and intracardiac repair implied a 1.7 higher risk of reoperation for bleeding compared with patients undergoing primary isolated bypass surgery. Logistic regression analysis predicted old age, combined procedure, early year of surgery and use of the internal mammary artery as risk factors of reoperation for bleeding. The risk of reoperation was not significantly related to number of grafts inserted or if the patient had undergone previous cardiac surgery. Reoperation for bleeding increased the stay in intensive care by at least one day but did not increase the risk of wound infection. CONCLUSIONS Special precautions seem indicated to reduce the risk of reoperation for bleeding in particularly elderly patients undergoing combined coronary surgery and other intracardiac repair.

Early and Late Patency of Aortocoronary Vein Grafts

Early patency (two weeks) of 331 aortocoronary vein grafts was 89%. Late patency (one year) of 122 restudied grafts was 80%. A cumulative one year patency of 72% was calculated. Patency was similar for SV grafts, sutured distal to stenosis and segmental obstruction. Early patency was significantly decreased when the peroperative graft blood flow was 20 ml/min or less or the diameter of the recipient coronary artery was smaller than 1.5 mm. Cumulative one year patency was lower in symptomatic patients (54%) than in those who underwent consecutive reevaluation (80%). There was a trend towards improved patency rates for graft anastomosed to the left anterior descending coronary artery and grafts without pre-existing pathological changes. Patient parameters, such as at operation, sex, smoking habits, hypertension, lipid abnormalities, diabetes, previous myocardial infarction or depressed left ventricular function, had no bearing on patency. Graft failure occurring, despite refined surgical technique, is usually due to pathological changes of the vein graft per se or the recipient coronary artery and its vascular bed.

Coronary artery bypass grafting-related bleeding complications in patients treated with ticagrelor or clopidogrel: a nationwide study

Abstract Aims Excessive bleeding impairs outcome after coronary artery bypass grafting (CABG). Current guidelines recommend withdrawal of clopidogrel and ticagrelor 5 days (120 h) before elective surgery. Shorter discontinuation would reduce the risk of thrombotic events and save hospital resources, but may increase the risk of bleeding. We investigated whether a shorter discontinuation time before surgery increased the incidence of CABG-related major bleeding complications and compared ticagrelor- and clopidogrel-treated patients. Methods and results All acute coronary syndrome patients in Sweden on dual antiplatelet therapy with aspirin and ticagrelor (n = 1266) or clopidogrel (n = 978) who underwent CABG during 2012–13 were included in a retrospective observational study. The incidence of major bleeding complications according to the Bleeding Academic Research Consortium-CABG definition was 38 and 31%, respectively, when ticagrelor/clopidogrel was discontinued <24 h before surgery. Within the ticagrelor group, there was no significant difference between discontinuation 72–120 or >120 h before surgery [odds ratio (OR) 0.93 (95% confidence interval, CI, 0.53–1.64), P = 0.80]. In contrast, clopidogrel-treated patients had a higher incidence when discontinued 72–120 vs. >120 h before surgery (OR 1.71 (95% CI 1.04–2.79), P = 0.033). The overall incidence of major bleeding complications was lower with ticagrelor [12.9 vs. 17.6%, adjusted OR 0.72 (95% CI 0.56–0.92), P = 0.012]. Conclusion The incidence of CABG-related major bleeding was high when ticagrelor/clopidogrel was discontinued <24 h before surgery. Discontinuation 3 days before surgery, as opposed to 5 days, did not increase the incidence of major bleeding complications with ticagrelor, but increased the risk with clopidogrel. The overall risk of major CABG-related bleeding complications was lower with ticagrelor than with clopidogrel.

Elevated glycosylated haemoglobin (HbA1c) is a risk marker in coronary artery bypass surgery

Objective. To evaluate if glycosylated haemoglobin 1 (HbA1c) was associated with increased risk of infection and mortality after coronary artery bypass grafting (CABG). Design. Prospective observational study. Preoperative HbA1c concentrations were correlated to outcome in patients followed for an average of 3.5 years after CABG. Results. HbA1c was ≥6% in 68% of 161 patients with diabetes mellitus (DM) and in 3% of 444 patients without DM. Superficial sternal wound infection was observed in 13.9% if HbA1c ≥6% versus in 5.5% if <6% (p=0.007). Mediastinitis occurred in 4.9% if HbA1c≥6% and in 2.1% if HbA1c<6% (p=0.20) (Hazard ratio (HR) 1.9, 95% CI 0.6-5.9). Follow-up mortality was 18.9% in patients with HbA1c≥6% compared to 4.1% if HbA1c<6% (p<0.001) with HR 5.4, (95% CI 3.0-10.0) after multivariable adjustment. The risk of death was similar regardless of DM diagnosis. Conclusions. HbA1c ≥6% was associated with an increased risk of postoperative superficial sternal wound infections and a trend for higher mediastinitis rate and significantly higher mortality three years after CABG.

Central Nervous System Damage During Cardiac Surgery Assessed by 3 Different Biochemical Markers in Cerebrospinal Fluid

Three cerebral biochemical markers, adenylate kinase (AK), neuron-specific enolase (NSE) and protein S-100, were determined in the cerebrospinal fluid (CSF) of male patients 24 h after coronary artery bypass grafting to investigate the extent of possible center nervous system (CNS) damage and relation to the type of oxygenator and the use of an arterial line filter. The patients were randomized into three groups for extracorporeal circulation (ECC); bubble oxygenator without an arterial line filter (Group I, n = 30), bubble oxygenator with a filter (Group II, n = 29) and a flat-sheet membrane oxygenator without a filter (Group III, n = 33). Pathologically high CSF levels of AK and NSE were found 24 h after ECC in respectively 93% and 95% of the patients. All protein S-100 concentrations were within the normal range. Isolated high CSF concentrations of AK, NSE and protein S-100 were observed in group I. Levels of AK and NSE were the lowest in group III, although there was no statistical difference between the groups. In conclusion, our study suggested that CNS damage caused by ECC involved neurons rather than glial cells. AK and NSE in the CSF seemed to be markers of ischaemic neuronal damage. Postoperative levels of biochemical markers in the CSF tended to be the lowest in the flat-sheet membrane oxygenator group.

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.