[Perioperative stroke after aortic valve replacement for aortic stenosis - incidence, risk factors and short-term outcome].

INTRODUCTION: One of the most serious complications of surgical aortic valve replacement (SAVR) is stroke that can result in increased rates of complications, morbidity and mortality postoperatively. The aim of this study was to investigate incidence, risk factors and short-term outcome in a well defined cohort of SAVR-patients. MATERIALS AND METHOD: A retrospective study on 740 consecutive aortic stenosis patients who underwent SAVR in Iceland 2002-2019. Patients with stroke were compared with non-stroke patients; including preoperative risk factors of cardiovascular disease, echocardiogram-results, rate of early postoperative complications other than stroke and 30 day mortality. RESULTS: Mean age was 71 yrs (34% females) with 57% of the patients receiving stented bioprosthesis, 31% a stentless Freestyle®-valve and 12% a mechanical valve. Mean EuroSCORE-II was 3.6, with a maximum preop-gradient of 70 mmHg and an estimated valvular area of 0.73 cm2. Thirteen (1.8%) patients were diagnosed with stroke where hemiplegia (n=9), loss of consciousness (n=3) and/or aphasia (n=4) were the most common presenting symptoms. In 70% of cases the neurological symptoms resolved or disappeared in the first weeks and months after surgery. Only one patient out of 13 died within 30-days (7.7%). Stroke-patients had significantly lower BMI than non-stroke patients, but other risk factors of cardiovascular diseases, intraoperative factors or the rate of other severe postoperative complications than stroke were similar between groups. Total length of stay was 14 days vs. 10 days median, including 2 vs. 1 days in the ICU, in the stroke and non-stroke-groups, respectively. CONCLUSIONS: The rate of stroke after SAVR was low (1.8%) and in line with other similar studies. Although a severe complication, most patients with perioperative stroke survived 30 days postoperatively and in majority of cases neurological symptoms recovered.

[Incidence and outcomes of perioperative myocardial infarction associated with coronary artery bypass surgery].

INTRODUCTION: Perioperative myocardial infarction (PMI) after CABG can contribute to in-hospital morbidity and mortality, however, its clinical significance on long-term outcome, remains inadequately addressed. We studied both 30-day mortality and long-term effects of PMI in Icelandic CABG-patients. MATERIALS AND METHODS: A retrospective nationwide-study on 1446 consecutive CABG-patients operated at Landspitali in Iceland 2002-2018 without evidence of preoperative myocardial infarction. PMI was defined as a tenfold elevetion in serum-CK-MB associated with new ECG changes or diagnostic imaging consistent with ischemia. Patients with PMI were compared to a reference group with uni- and multivariate analyses. Long-term and MACCE-free survival were estimated with the Kaplan-Meier method and logistic regression used to determine factors associated with PMI. The mean follow-up time was 8.3 years. RESULTS: Out of 1446 patients 78 (5.4%) were diagnosed with PMI (range: 0-15.5%) with a significant annual decline in the incidence of PMI (12.7%, p<0.001). Over the same period preoperative aspirin use increased by 22.3% (p<0.018). PMI patients had a higher rate of short-term complications and a 11.5% 30-day mortality rate compared to 0.4% for non-PMI patients. PMI was found to be a predictor of 30-day mortality (OR 15.44, 95% CI: 6.89-34.67). PMI patients had worse 5-year MACCE-free survival (69.2% vs. 84.7, p=0,01), although overall survival was comparable between the groups. CONCLUSIONS: Although PMI after CABG is associated with significantly higher rates of short-term complications and 30-day mortality, long-term survival was similar to the reference group. Therefore, the mortality risk attributable to PMI appears to diminish after the immediate postoperative period.

[The effect of obesity on the outcome of surgical aortic valve replacement for aortic stenosis].

INTRODUCTION: Our objective was to investigate the effect of obesity on short-term complications and long-term survival after surgical aortic valve replacement (SAVR) for aortic stenosis (AS). MATERIAL AND METHODS: A retrospective study on 748 patients who underwent SAVR for AS in Iceland 2003-2020. Patients were divided into groups based on body mass index (BMI): normal (18.5-24.9 kg/m2, n=190), overweight (25-29.9 kg/m2, n=339), obese (30-34.9 kg/m2, n=165) and severely obese (≥35 kg/m2, n=54). Six patients with BMI p<18,5 kg/m2 were excluded. Clinical information regarding patient history, risk factors, together with complications and 30-day mortality were collected from patient records. The four BMI groups were compared and long-term survival estimated with Kaplan-Meier plots and risk factors for long-term survival evaluated with Cox multivariate analysis. RESULTS: Severely obese patients were on average four years younger than patients with normal BMI, more often had risk factors for cardiovascular disease, and their EuroSCORE II was higher (5.3 vs. 4.4%, p=0.03). On the other hand, severely obese patients bled less the first 24 hours post-surgery, compared to normal BMI-patients (558 vs. 1091 ml, p<0.001), stroke was less frequent (0 vs 6.4%, p=0.03), but they more often experienced sternum dehiscence (5.6 vs 2.7%, p=0.04), deep sternal wound infection (3.7 vs 0%, p=0.04) and acute kidney injury (26.4 vs 15.2%, p=0.005). Thirty-day mortality and long-term survival did not differ significantly between the groups and BMI was not an independent predictor of long-term survival in multivariate analysis. CONCLUSIONS: The outcome for obese patients undergoing SAVR for AS is good and both short-term complications and long-term survival do not differ significantly from patients with a normal BMI. Therefore, a high BMI itself should not be a contraindication for SAVR due to AS.

[Incidence and predictors of prolonged intensive care unit stay after coronary artery bypass in Iceland].

INTRODUCTION: To maximize the use of intensive care unit (ICU) re--sources, it is important to estimate the prevalence and risk factors for prolonged ICU unit stay after coronary artery bypass grafting (CABG) surgery. MATERIAL AND METHODS: This retrospective cohort study included all patients who underwent primary isolated CABG at Landspitali between 2001 and 2018. Patient information was collected from hospital charts and death registries. Patients who stayed in the ICU for the conventional one night postoperatively were compared with those who needed longer stays in the ICU. Survival rate was estimated with the Kaplan-Meier method. Predictors for prolonged ICU stay were calculated with logistic regression and the outcome used to create a calculator that estimates the probability of prolonged ICU stay. RESULTS: Out of 2177 patients, 20% required prolonged ICU stay. Patients with prolonged stay were more frequently female (23% vs 16%, p=0.001), had a higher rate of cardiovascular risk factors and higher EuroSCORE II (4.7 vs. 1.9, p<0.001). They also had a higher rate of impaired renal function before surgery (14% vs. 4%, p<0.001) and emergent surgery (18% vs. 2%, p<0.001). Furthermore, these patients had higher rates of both short-term and long-term complications, and lower long-term survival (85% vs 68% five-year survival rate, p<0.0001). Independent risk factors for prolonged ICU stay were advanced age, female gender, EuroSCORE II, history of heart diseases, impaired renal function and emergent surgery.  Conclusions: Every fifth patient had a prolonged ICU stay after CABG. Several risk factors predicted prolonged ICU stay after CABG, in particular patients' medical condition before surgery, EuroSCORE II and emergent surgery. A better understanding of the risk factors for prolonged ICU stay will hopefully aid in scheduling CABG surgeries at Landspitali.

[The use of Intra Aortic Balloon Pump in Coronary Artery Bypass Graft Surgery].

INTRODUCTION: Intra-aortic balloon pump (IABP) is a mechanical device that increases cardiac output by increasing diastolic blood flow to the coronary arteries and lowers the afterload of the left ventricle in systole. IABP is primarily used in acute heart failure, that includes patients that have to undergo coronary artery bypass grafting (CABG). Its usage, however, in cardiac surgery has been declining with ongoing controversy regarding its benefits. The aim of this study was to assess the use and indications and outcome of IABP related to CABG surgery. MATERIAL AND METHODS: The study was retrospective and included 2177 patients that underwent CABG at Landspítali during 2001-2018. We compared those who received an IABP with controls, using uni- and multivariate analysis. Long term survival and complications (major adverse cardiovascular and cerebral events, MACCE) was estimated with Kaplan-Meier method. RESULTS: A total of 99 (4.5%) patients received an IABP. The incidence was highest in 2006 (8.9%) and lowest in 2001 (1.7%), but the incidence did not change during the study period (p=0.90). Most patients received the pump before (58.6%) or during (34.3%) CABG, but only 6.1% after surgery. Complication rate was 14.1%, with bleeding from the insertion site in the groin being the most common complication. Thirty day mortality was higher in the IABP group compared with controls (22.2% vs 1.3%, p<0.001) and both 5-year survival (56.4% vs 91.5%, 95% CI: 0.47-0.67) and 5-year MACCE-free survival (46.9% vs 83.0%, 95% CI: 0.38-0.58) were inferior. CONCLUSIONS: Less than 5% of patients received IABP in relation to CABG in Iceland and the rate hasn't changed much for the last 18 years. Both the complication rate and 30-day mortality was higher in patients in IABP group and both the long term and MACCE-free survival was much worse, probably mostly related to worse overall clinical condition of the patient that received IABP.