Disparities in cardiovascular disease and treatment in the Nordic countries.

The Nordic countries, including Denmark, Finland, Iceland, Norway, and Sweden have seen a steep decline in cardiovascular mortality in recent decades. They are among the most egalitarian countries by several measures, and all have universal, publicly funded welfare systems providing healthcare for all citizens. However, despite these seemingly ideal conditions, disparities in access to cardiovascular care and outcomes persist. To address this challenge, The Lancet Region Health-Europe convened experts from a broad range of countries to summarize the current state of knowledge on cardiovascular disease disparities across Europe. This Series Paper presents the main challenges in Nordic countries based on evidence from high-quality nationwide registries. Focusing on major cardiovascular health determinants, areas in need of improvement were identified. There is a need for addressing structural causes underlying these disparities, such as poverty and discrimination, but also to improve access to healthcare in deprived neighborhoods and to address underlying social determinants of health that may mitigate disparities in cardiovascular outcomes. Overall, while the Nordic countries have made great strides in promoting egalitarianism and providing universal healthcare, there is still much work to be done to ensure equitable access to care and improved cardiovascular outcomes for all members of society.

Myocardial Flow Reserve, an Independent Prognostic Marker of All-Cause Mortality Assessed by 82Rb PET Myocardial Perfusion Imaging: A Danish Multicenter Study.

BACKGROUND: Rubidium-82 positron emission tomography (82Rb PET) myocardial perfusion imaging is used in clinical practice to quantify regional perfusion defects. Additionally, 82Rb PET provides a measure of absolute myocardial flow reserve (MFR), describing the vasculature state of health. We assessed whether 82Rb PET-derived MFR is associated with all-cause mortality independently of the extent of perfusion defects. METHODS: We conducted a multicenter clinical registry-based study of patients undergoing 82Rb PET myocardial perfusion imaging on suspicion of chronic coronary syndromes. Patients were followed up in national registries for the primary outcome of all-cause mortality. Global MFR ≤2 was considered reduced. RESULTS: Among 7169 patients studied, 38.1% were women, the median age was 69 (IQR, 61-76) years, and 39.0% had MFR ≤2. A total of 667 (9.3%) patients died during a median follow-up of 3.1 (IQR, 2.6-4.0) years, more in patients with MFR ≤2 versus MFR >2 (15.7% versus 5.2%; P<0.001). MFR ≤2 was associated with all-cause mortality across subgroups defined by the extent of perfusion defects (all P<0.05). In a Cox survival regression model adjusting for sex, age, comorbidities, kidney function, left ventricular ejection fraction, and perfusion defects, MFR ≤2 was a robust predictor of mortality with a hazard ratio of 1.62 (95% CI, 1.31-2.02; P<0.001). Among patients with no reversible perfusion defects (n=3101), MFR ≤2 remained strongly associated with mortality (hazard ratio, 1.86 [95% CI, 1.26-2.73]; P<0.01). The prognostic value of impaired MFR was similar for cardiac and noncardiac death. CONCLUSIONS: MFR ≤2 predicts all-cause mortality independently of the extent of perfusion defects. Our results support the inclusion of MFR when assessing the prognosis of patients suspected of chronic coronary syndromes.

Coronary Microvascular Disease Assessed by 82-Rubidium Positron Emission Tomography Myocardial Perfusion Imaging Is Associated With Small Vessel Disease of the Kidney and Brain.

Background Coronary microvascular disease (CMD) may be part of a systemic small vessel disease that also manifests as neurological impairment and kidney disease. However, clinical evidence supporting a potential link is scarce. We assessed whether CMD is associated with an increased risk of small vessel disease in the kidney and brain. Methods and Results A retrospective multicenter (n=3) study of patients clinically referred to 82-rubidium positron emission tomography myocardial perfusion imaging was conducted between January 2018 and August 2020. Exclusion criterion was reversible perfusion defects >5%. CMD was defined as myocardial flow reserve (MFR) ≤2. The primary outcome, microvascular event, was defined by hospital contact for chronic kidney disease, stroke, or dementia. Among 5122 patients, 51.7% were men, median age 69.0 [interquartile range, 60.0-75.0] years, 11.0% had left ventricular ejection fraction ≤40%, and 32.4% had MFR ≤2. MFR was associated with baseline estimated glomerular filtration rate after multivariable adjustment (ß=0.04 [95% CI, 0.03-0.05]; P<0.001). During a median follow-up of 3.05 years, 383 (7.5%) patients suffered an event (253 cerebral and 130 renal), more frequently in patients with MFR ≤2 versus MFR >2 (11.6% versus 5.5%, P<0.001). MFR ≤2 was associated to outcome with a hazard ratio (HR) of 2.30 (95% CI, 1.88-2.81, P<0.001) and an adjusted HR of 1.62 (95% CI, 1.32-2.00, P<0.001). Results were consistent across subgroups defined by presence of irreversible perfusion defects, estimated glomerular filtration rate, diabetes, left ventricular ejection fraction, and previous revascularization. Conclusions This is the first large-scale cohort study to link CMD to microvascular events in the kidney and brain. Data support the hypothesis that CMD is part of a systemic vascular disorder.

Prognostic implications of myocardial perfusion imaging by 82-rubidium positron emission tomography in male and female patients with angina and no perfusion defects.

AIMS: Myocardial perfusion imaging with 82-rubidium positron emission tomography (82Rb-PET) is increasingly used to assess stable coronary artery disease (CAD). We aimed to evaluate the prognostic value of 82Rb-PET-derived parameters in patients with symptoms suggestive of CAD but no significant reversible or irreversible perfusion defects. METHODS AND RESULTS: Among 3726 consecutive patients suspected of stable CAD who underwent 82Rb-PET between January 2018 and August 2020, 2175 had no regional perfusion defects. Among these patients, we studied the association of 82Rb-PET-derived parameters with a composite endpoint of all-cause mortality, hospitalization for unstable angina pectoris, acute myocardial infarction, heart failure, or ischaemic stroke. During a median follow up of 1.7 years (interquartile range 1.1-2.5 years), there were 148 endpoints. Myocardial blood flow (MBF) reserve (MFR), MBF during stress, left ventricular ejection fraction (LVEF), LVEF-reserve, heart rate reserve, and Ca score were associated with adverse outcomes. In multivariable Cox model adjusted for patient and 82Rb-PET characteristics, MFR < 2 (hazard ratio (HR) 1.75, 95% confidence interval (CI) 1.24-2.48), LVEF (HR 1.38 per 10% decrease, 95% CI 1.24-1.54), and LVEF-reserve (HR 1.19 per 5% decrease, 95% CI 1.07-1.31) were significant predictors of endpoints. Results were consistent in subgroups defined by gender, history of ischaemic heart disease, low LVEF, and atrial fibrillation. CONCLUSION: MFR, LVEF, and LVEF-reserve derived from 82Rb-PET provide prognostic information on cardiovascular outcomes in patients with no perfusion defects. This may aid in identifying patients at risk and might provide an opportunity for preventive interventions.