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➤ Diagnosis
• Diagnostic criteria for ASCVD include a history of myocardial
infarction, stroke, coronary revascularization, or angiographic
evidence of ≥50% stenosis; probable ASCVD is suggested by stable
angina with positive ischemic testing, a coronary artery calcium
score ≥100 Agatston units, or an ankle-brachial index <0.9. In obesity,
risk stratification is enhanced by biomarkers such as elevated high-
sensitivity C-reactive protein (>2 mg/L) or lipoprotein (a) ≥50 mg/dL.
Heart Failure (HF)
➤ Obesity contributes to HF, particularly HF with preserved ejection
fraction (HFpEF), by increasing blood volume and cardiac output
and by promoting systemic inflammation, with visceral adiposity
exacerbating both systolic and diastolic dysfunction, despite the
debated "obesity paradox."
Risk Factors
• Modifiable risk factors include obesity (each 5 kg/m² increase in BMI
raises risk by 29%), with visceral adiposity being a robust predictor,
as well as hypertension, which affects over 70% of patients with
obesity and accelerates left ventricular hypertrophy. Additional
contributors include diabetes mellitus and insulin resistance, which
foster myocardial injury through impaired glucose utilization and
lipotoxicity, dyslipidemia with elevated free fatty acids, obstructive
sleep apnea (prevalent in 40% to 60% of adults with obesity), physical
inactivity, and diets high in saturated fat and sugar. Nonmodifiable
factors encompass older age (with risk doubling each decade after
40), genetic variants such as PNPLA3 and TM6SF2, sex (women are
more prone to HFpEF due to hormonal influences), and ethnicity, as
Black and Hispanic populations exhibit higher HF incidence related
to both biological and social determinants.
➤ Clinical Manifestations
• HF presents across a spectrum, with clinical features classified
based on the predominant ventricle involved. Left-sided HF usually
presents with exertional dyspnea that progresses to orthopnea and
paroxysmal nocturnal dyspnea, along with fatigue and weakness
from reduced cardiac output, and pulmonary congestion, evidenced
by rales and wheezing. Right-sided HF is marked by peripheral
edema, jugular venous distension, and signs of venous congestion
such as hepatomegaly and ascites. The presence of comorbidities,
including obstructive sleep apnea, type 2 diabetes mellitus, and
chronic kidney disease, further worsens symptoms. Notably, although
higher BMI has been linked to better survival in established HF (the
obesity paradox), possibly due to metabolic reserves or selection bias,
intentional weight loss still provides benefits and improves outcomes.
Coexisting conditions like obstructive sleep apnea, T2DM, and chronic
kidney disease increase symptom burden.
