Thomas Mooe

Increased Risk of Stroke in Patients With Coronary Artery Disease and Sleep Apnea: A 10-Year Follow-Up

Background— The effect of sleep apnea on mortality and cardiovascular morbidity is mainly unknown. We aimed to study whether sleep apnea is related to stroke, death, or myocardial infarction in patients with symptomatic coronary artery disease. Methods and Results— A total of 392 men and women with coronary artery disease referred for coronary angiography were examined by use of overnight sleep apnea recordings. Sleep apnea, defined as an apnea-hypopnea index ≥5, was recorded in 54% of the patients. All patients were followed up prospectively for 10 years, and no one was lost to follow-up. Stroke occurred in 47 (12%) of 392 patients during follow-up. Sleep apnea was associated with an increased risk of stroke, with an adjusted hazard ratio of 2.89 (95% confidence interval 1.37 to 6.09, P=0.005), independent of age, body mass index, left ventricular function, diabetes mellitus, gender, intervention, hypertension, atrial fibrillation, a previous stroke or transient ischemic attack, and smoking. Patients with an apnea-hypopnea index of 5 to 15 and patients with an apnea-hypopnea index ≥15 had a 2.44 (95% confidence interval 1.08 to 5.52) and 3.56 (95% confidence interval 1.56 to 8.16) times increased risk of stroke, respectively, than patients without sleep apnea, independent of confounders (P for trend=0.011). Death and myocardial infarction were not related to sleep apnea. Intervention in the form of coronary artery bypass grafting or percutaneous coronary intervention was related to a longer survival but did not affect the incidence of stroke. Conclusions— Sleep apnea is significantly associated with the risk of stroke among patients with coronary artery disease who are being evaluated for coronary intervention.

Sleep-disordered breathing: a novel predictor of atrial fibrillation after coronary artery bypass surgery

BACKGROUND Sleep-disordered breathing is a common condition associated with nocturnal hypoxaemia, sympathetic activation and haemodynamic stress that can trigger arrhythmias. We examined whether preoperatively diagnosed disordered breathing was associated with an increased incidence of atrial fibrillation after coronary artery bypass surgery. METHODS A sleep study was performed in 121 consecutive patients, who were monitored prospectively until discharge from hospital after surgery. Disordered breathing was defined as an apnoea-hypopnoea index (AHI) > or = 5 or an oxygen desaturation index (ODI) > or = 5. All episodes of atrial fibrillation requiring pharmacological intervention or cardioversion were included in the analysis. RESULTS Atrial fibrillation was diagnosed in 32% of patient with AHI > or = 5 (25 of 78) and in 18% patients with AHI < 5 (7 of 39, P = 0.11). Similarly, atrial fibrillation was diagnosed in 39% of patients with ODI > or = 5 (19 of 49) and in 18% of patients with ODI < 5 (13 of 72, P = 0.02). In a multiple-logistic regression model including age, left ventricular function, aortic cross clamp time, maximum postoperative level of lactate dehydrogenase and disordered breathing (ODI > or = 5), greater age and disordered breathing were independent predictors of postoperative atrial fibrillation. The relative risk of atrial fibrillation was 2.0 (95% confidence interval 1.1-3.8) for a 10-year increase in age and 2.8 (95% confidence interval 1.2-6.8) for disordered breathing (ODI > or = 5). CONCLUSIONS Pre-operatively diagnosed sleep-disordered breathing with nocturnal hypoxaemia is an independent predictor of atrial fibrillation after coronary bypass surgery.

Sleep-disordered breathing in women: occurrence and association with coronary artery disease.

PURPOSE To examine the occurrence of sleep apnea and nocturnal hypoxemia in women with and without coronary artery disease (CAD) and to investigate the relationship between sleep-disordered breathing and coronary artery disease. PATIENTS AND METHODS In a case-control study, 102 cases were randomly selected among women with angina pectoris and angiographically verified coronary disease. Fifty age-matched controls without known heart disease were selected from the population registry. Pulse oximetry, oronasal thermistors, body position indicator, and recording of body and respiratory movements were used to quantify oxygen desaturations (the number of desaturations > or = 4% per hour of sleep, oxygen desaturation index [ODI]) and apneas (the number of apneas or hypopneas per hour of sleep, apnea-hypopnea index [AHI]). RESULTS Women with CAD had a high occurrence of disordered breathing measured as AHI > or = 5, 54% (n = 54), AHI > or = 10, 30% (n = 30) or ODI > or = 5, 34% (n = 35) while the same proportions in controls were 20% (n = 10, P < 0.0001), 10% (n = 5, P < 0.01) and 18% (n = 9, P < 0.05), respectively. In a multiple logistic regression model, sleep apnea (AHI > or = 5), hypertension, and smoking habits were independent predictors of CAD with odds ratios of 4.1 (95% confidence interval [CI] 1.7 to 9.7, P < 0.01), 3.4 (CI 1.3 to 8.9, P < 0.05) and 2.4 (CI 1.0 to 5.7, P < 0.05), respectively. CONCLUSION Sleep apnea is common in women with CAD and remains as a significant predictor of coronary disease after adjustment for age, body mass index, hypertension, smoking habits, and diabetes.

Ischemic Stroke After Acute Myocardial Infarction: A Population-Based Study

BACKGROUND AND PURPOSE Modern treatment may have influenced the risk of stroke after myocardial infarction (MI). The purpose of this study was to examine the incidence of ischemic stroke during the first month after an acute MI in an unselected population, to identify predictors of MI-related stroke, and to investigate the secular trend in MI-related stroke incidence. METHODS In this case-control study, from a population of approximately 310000 25- to 74-year-old inhabitants, case subjects with a stroke within 1 month after an MI were prospectively recorded in the population-based Northern Sweden MONICA (Monitoring of Trends and Determinants in Cardiovascular Disease) study from 1985 to 1994. The same number of control subjects with an MI but without a stroke were matched for age, sex, and year when MI occurred. RESULTS One hundred twenty-four case subjects were recorded. Fifty-one percent (63/124) of the strokes occurred within 5 days after onset of MI. The odds ratios (ORs) of an MI-related stroke were for a history of hypertension 1.7 (95% confidence interval [CI], 1.0 to 3.2), previous stroke 2.4 (CI, 1.0 to 6.1), chronic atrial fibrillation 3.0 (CI, 1.1 to 9.2), onset of atrial fibrillation during the hospital stay 3.5 (CI, 1.4 to 10.1), ST-segment elevation 2.4 (CI, 1.4 to 4.6), and anterior infarction 1.5 (CI, 0.9 to 2.6). In a conditional multiple logistic regression model, previous stroke (OR, 2.8; CI, 1.1 to 7.6), chronic atrial fibrillation (OR, 3.8; CI, 1.3 to 11.0), new-onset atrial fibrillation (OR, 4.6; CI, 1.6 to 12.8), and ST-segment elevation (OR, 3.4; CI, 1.6 to 7.4) were independent predictors of stroke. MIs preceding stroke were larger and in 51% were located anteriorly. There was a decrease in the incidence and event rate of MI-related stroke during the study period (P < .01 and P < .05, respectively). CONCLUSIONS The risk of stroke is highest the first 5 days after MI. Only approximately half of the strokes occurring the first month after an MI are preceded by an anterior MI. The most important predictors of MI-related stroke are atrial fibrillation (chronic or new onset), ST elevation, and a history of a previous stroke. There is a long-term trend toward a lower incidence of MI-related stroke. These findings have important implications concerning both the pathophysiology and prevention of MI-related stroke.

Ischemic Stroke Impact of a Recent Myocardial Infarction

BACKGROUND AND PURPOSE The risk of ischemic stroke is increased after a myocardial infarction. We quantified the stroke risk and evaluated ischemic stroke characteristics after an acute myocardial infarction. METHODS A case-control study including patients with first-ever stroke was undertaken. Cases (n=103) were recorded prospectively in the population-based Northern Sweden World Health Organization Multinational Monitoring of Trends and Determinants in Cardiovascular Disease (MONICA) study. Two controls per case with a stroke but without a recent myocardial infarction were matched for age, sex, and year of stroke onset. RESULTS The sudden onset of neurological symptoms (76.7% versus 54.9%, P<0.001), impairment of consciousness (35.0% versus 18.4%, P<0.01), and a progression in neurological deficits (19.4% versus 8.7%, P<0.01) were more common in cases, while the onset of stroke during sleep was rarer in cases (6.8% versus 21.4%, P<0.01). In cases and controls, the clinical subclasses of stroke were as follows: total anterior circulation infarcts, 51.5% versus 37.9% (P<0.05); partial anterior circulation infarcts, 28.2% versus 26.7% (P=NS); lacunar infarcts, 4.8% versus 27.2% (P<0.001); and posterior circulation infarcts, 15.5% versus 8.2% (P=0.051). During the first 28 days after myocardial infarction, the daily rate of stroke declined rapidly from approximately 9 to 1 stroke per 10 000 myocardial infarction patients compared with an age-adjusted average daily stroke rate of 0.14 per 10 000 in the MONICA population. CONCLUSIONS We conclude that the clinical characteristics of the stroke differ between patients with and without a recent myocardial infarction. The risk of a first-ever ischemic stroke is highest during the first few days after a myocardial infarction, but it then declines rapidly, and the absolute number of stroke events is low.

Platelet aggregation and aspirin non‐responsiveness increase when an acute coronary syndrome is complicated by an infection

Background: Epidemiologic studies have shown that there is an association between acute respiratory infection and acute coronary syndrome. The aim of this study was to analyze the thrombotic risk, assessed by platelet aggregation and aspirin non‐responsiveness, in patients with an acute coronary syndrome complicated by an infection. Methods: Patients with an acute coronary syndrome who were admitted to the intensive care unit and hospitalized for at least 3 days in 2002 and 2003 were eligible for the study. Three hundred and fifty‐eight patients were included, of whom 66 had an infection during their hospital stay. Platelet aggregation was analyzed by an aggregometer using laser light (PA‐200, laser light scattering). Aspirin non‐responsiveness was defined as a closure time of ≤193 s measured by PFA‐100. Results: Platelet aggregation was more pronounced during an infectious complication (P < 0.001). The subgroups of patients with persistent fever, urinary tract infection, and pneumonia all had a higher level of aggregates than the group of patients without an infection (P = 0.007, P = 0.04, and P = 0.01, respectively). Aspirin non‐responsiveness was more frequent in the group of subjects with pneumonia compared with those without an infection, 90% vs. 46% (P = 0.006). The CRP levels were independently associated with platelet aggregation and aspirin non‐responsiveness (P < 0.001, P < 0.001, respectively). Conclusion: An infectious complication during the course of an acute coronary syndrome leads to more pronounced platelet aggregation. Aspirin non‐responsiveness is more frequent in severe infections, such as pneumonia. CRP is an independent predictor of platelet aggregation and aspirin non‐responsiveness in the setting of an acute coronary syndrome.

Incidence, Trends, and Predictors of Ischemic Stroke 30 Days After an Acute Myocardial Infarction

Background and Purpose— Ischemic stroke is a known complication of acute myocardial infarction (AMI). Treatment of AMI has undergone great changes in recent years. We aimed to investigate whether changes in treatment corresponded to a lower incidence of ischemic stroke and which factors predicted ischemic stroke after AMI. Methods— Data were taken from the Swedish Register of Information and Knowledge about Swedish Heart Intensive Care Admissions. Patients with their first registered AMI between 1998 and 2008 were included. To identify ischemic strokes, we used the Swedish national patient register. To study a potential trend in the incidence of ischemic stroke after AMI over time, we divided the patient population into 5 time periods. Event-free survival was studied by Kaplan–Meier analysis. Cox proportional hazards regression model was used to identify stroke predictors. Results— Of 173 233 patients with AMI, 3571 (2.1%) developed ischemic stroke within 30 days. The incidence of ischemic stroke was significantly lower during the years 2007 to 2008 compared with 1998 to 2000, with respective rates of 2.0% and 2.2% (P=0.02). Independent predictors of an increased risk of stroke were age, female sex, prior stroke, diabetes mellitus, atrial fibrillation, clinical signs of heart failure in hospital, ST-segment–elevation myocardial infarction, coronary artery bypass grafting, and angiotensin-converting enzyme inhibitor treatment at discharge. Percutaneous coronary intervention, fibrinolysis, acetylsalicylic acid, statins, and P2Y12 inhibitors were predictors of reduced risk of stroke. Conclusions— The incidence of ischemic stroke within 30 days of an AMI has decreased during the period 1998 to 2008. This decrease is associated with increased use of acetylsalicylic acid, P2Y12 inhibitors, statins, and percutaneous coronary intervention.

Dipyridamole thallium-201 single-photon emission tomography in aortic stenosis: gender differences.

Dipyridamole single-photon emission tomography (SPET) is used for the detection of coronary artery disease (CAD) and the method has also been applied in patients with aortic stenosis. This study was undertaken to establish the gender-specific normal limits of thallium-201 distribution in patients with aortic stenosis and to apply these normal limits in a larger group of patiens with aortic stenosis to obtain the sensitivity and specificity for coexisting CAD. A low-dose dipyridamole protocol was used (0.56 mg/kg during 4 min). Thallium was injected 2 min later and tomographic imaging was performed. Following image reconstruction a basal, a mid-ventricular and an apical short-axis slice were selected. The highest activity in each 6° segment was normalised to the maximal acitivity of each slice. The normal uptake for patients with aortic stenosis was obtained from ten men and ten women with aortic stenosis and a normal coronary angiography. Eighty-nine patients were prospectively evaluated. An area reduction of at least 75% in a coronary artery was considered to be a significant coronary lesion and was found in 57 (64%) patients. With gender-specific curves (-2.5 SD) sensitivity for detecting CAD was 100% and specificity was 75% in men, while sensitivity was 61% and specificity 64% in women. It is concluded that the gender-specific normal distribution of201T1 uptake in patients with aortic stenosis, using dipyridamole SPET, yields a high sensitivity and specificity for coronary artery lesions in men but a lower sensitivity and specificity in women with aortic stenosis.

Nurse-Led, Telephone-Based, Secondary Preventive Follow-Up after Stroke or Transient Ischemic Attack Improves Blood Pressure and LDL Cholesterol : Results from the First 12 Months of the Randomized, Controlled NAILED Stroke Risk Factor Trial

Background Enhanced secondary preventive follow-up after stroke or transient ischemic attack (TIA) is necessary for improved adherence to recommendations regarding blood pressure (BP) and low-density lipoprotein cholesterol (LDL-C) levels. We investigated whether nurse-led, telephone-based follow-up was more efficient than usual care at improving BP and LDL-C levels at 12 months after hospital discharge. Methods We randomized 537 patients to either nurse-led, telephone-based follow-up (intervention) or usual care (control). BP and LDL-C measurements were performed at 1 month (baseline) and 12 months post-discharge. Intervention group patients who did not meet target values at baseline received additional follow-up, including titration of medication and lifestyle counselling, to reach treatment goals (BP < 140/90 mmHg, LDL-C < 2.5 mmol/L). Results At 12 months, mean systolic BP, diastolic BP and LDL-C was 3.3 (95% CI 0.3 to 6.3) mmHg, 2.3 mmHg (95% CI 0.5 to 4.2) and 0.3 mmol/L (95% CI 0.1 to 0.4) lower in the intervention group compared to controls. Among participants with values above the treatment goal at baseline, the difference in systolic BP and LDL-C was more pronounced (8.0 mmHg, 95% CI 4.0 to 12.1, and 0.6 mmol/L, 95% CI 0.4 to 0.9). A larger proportion of the intervention group reached the treatment goal for systolic BP (68.5 vs. 56.8%, p = 0.008) and LDL-C (69.7% vs. 50.4%, p < 0.001). Conclusions Nurse-led, telephone-based secondary preventive follow-up, including medication adjustment, was significantly more efficient than usual care at improving BP and LDL-C levels by 12 months post-discharge. Trial Registration ISRCTN Registry ISRCTN23868518

Mortality After Ischemic Stroke in Patients With Acute Myocardial Infarction: Predictors and Trends Over Time in Sweden

Background and Purpose— Acute myocardial infarction (AMI) increases the risk of ischemic stroke, and mortality among these patients is high. Here, we aimed to estimate the 1-year mortality reliably after AMI complicated by ischemic stroke. We also aimed to identify trends over time for mortality during 1998–2008, as well as factors that predicted increased or decreased mortality. Methods— Data for 173 233 unselected patients with AMI were collected from the Swedish Register of Information and Knowledge about Swedish Heart Intensive Care Admissions registry for 1998–2008. Specifically, we analyzed 1-year follow-up and mortality data for patients with AMI with and without ischemic stroke. Kaplan–Meyer analysis was used to analyze mortality trends over time, and Cox regression analysis was used to identify uni- and multivariate predictors of mortality. Results— The 1-year mortality was 36.5% for AMI complicated by ischemic stroke and 18.3% for AMI without stroke. Mortality decreased over time in patients with and without ischemic stroke. The absolute decreases in mortality were 9.4% and 7.5%, respectively. Reperfusion and secondary preventive therapies were associated with a decreased mortality rate. Conclusions— Mortality after AMI complicated by an ischemic stroke is very high but decreased from 1998 to 2008. The increased use of evidence-based therapies explains the improved prognosis.