Causal Relationship Between Myocardial Infarction and Hypertension

Introduction to the Causal Relationship

The American Heart Association suggests that hypertension has a clear causal relationship with myocardial infarction through multiple pathophysiological mechanisms, and this relationship is bidirectional—hypertension increases MI risk, and a history of hypertension worsens outcomes after MI occurs 1, 2, 3

The European Society of Cardiology indicates that left ventricular hypertrophy, resulting from chronic pressure overload, decreases coronary reserve and increases myocardial oxygen demand, creating a supply-demand mismatch that precipitates ischemia 1
The American College of Cardiology recommends that increased recurrent events in patients with established coronary disease make blood pressure control essential for secondary prevention 1, 2

The American Heart Association states that traditional risk factors, including hypertension, have limited acute predictive value in patients presenting with possible acute coronary syndrome, and are less important than symptoms, ECG findings, and cardiac biomarkers for determining whether to admit or treat for ACS 4, 5
The European Society of Cardiology notes that once ACS is confirmed, a history of hypertension becomes a major adverse prognostic factor associated with poor outcomes and should guide aggressive management 4, 5
Hypertension is present in 50-54% of patients with NSTEMI, with higher prevalence in women, and these patients have higher rates of diabetes, prior MI, prior stroke, and heart failure 6

Vascular remodeling from sustained hypertension increases pulse wave velocity and central systolic pressure while decreasing diastolic pressure, compromising coronary perfusion, as noted by the European Heart Journal 7
The European Society of Cardiology suggests that achieving normotensive levels in treated hypertensive patients could prevent more than 15% of MIs in the treated hypertensive population, and that treatment trials demonstrate reductions in both recurrent MI and all-cause mortality 1, 2, 8, 3
The American College of Cardiology recommends that systolic blood pressure targets are important, as treatment trials demonstrate that cardiovascular events correlate more closely with achieved systolic pressure than diastolic pressure, and benefits extend even when initial blood pressure is <140/90 mmHg 1, 8, 3

The American Heart Association advises against using the presence or absence of hypertension to determine ACS admission, and instead recommends relying on symptoms, ECG, and biomarkers 4, 5
The European Society of Cardiology notes that avoiding excessive diastolic lowering in wide pulse pressure is crucial, as lowering systolic blood pressure may cause very low diastolic values, requiring careful assessment for myocardial ischemia symptoms 6