Blood Pressure in Pulmonary Embolism

Pathophysiology of Blood Pressure Changes in PE

Acute pulmonary embolism interferes with both circulation and gas exchange, with right ventricular failure due to acute pressure overload being the primary cause of death in severe cases, according to the European Respiratory Society 1
The abrupt increase in pulmonary vascular resistance results in right ventricular dilation and dysfunction, which alters the contractile properties of the right ventricular myocardium via the Frank-Starling mechanism, as reported by the European Respiratory Society 2
While compensatory mechanisms including systemic vasoconstriction temporarily stabilize systemic blood pressure, the extent of adaptation is limited as the thin-walled right ventricle cannot generate a mean pulmonary artery pressure >40 mmHg, as stated by the European Heart Society 3
Prolonged right ventricular contraction time leads to leftward bowing of the interventricular septum, causing desynchronization of the ventricles and impeded left ventricular filling in early diastole, according to the European Respiratory Society 2
This cascade ultimately leads to reduced cardiac output and contributes to systemic hypotension and hemodynamic instability in severe pulmonary embolism, as reported by the European Heart Society 3

Sustained hypotension is a defining feature of massive pulmonary embolism, with a 90-day mortality rate of 52.4% versus 14.7% in normotensive patients, as stated by the American Heart Association in Circulation 4
Hypotension in pulmonary embolism is associated with significantly increased mortality, with the American Heart Association recommending close monitoring of blood pressure in these patients 4

Arterial hypertension is actually listed as a weak risk factor for developing venous thromboembolism, rather than being a consequence of pulmonary embolism, as reported by the European Respiratory Society and the European Heart Society 1, 5
There is no evidence suggesting that high blood pressure occurs as a direct result of acute pulmonary embolism, according to the European Respiratory Society and the European Heart Society 1, 2, 3

Blood pressure monitoring is crucial in pulmonary embolism patients as hypotension is a critical marker of severity and poor prognosis, as stated by the American Heart Association in Circulation 4
High-risk pulmonary embolism is defined by hemodynamic instability including hypotension, pulselessness, or persistent profound bradycardia, according to the European Respiratory Society 1
Systemic hypotension in pulmonary embolism can further compromise the situation by impairing coronary driving pressure to the already overloaded right ventricle, potentially leading to right ventricular ischemia, as reported by the European Heart Society 3

In some cases, unresolved pulmonary embolism can lead to chronic thromboembolic pulmonary hypertension, but this refers to pulmonary hypertension, not systemic hypertension, as stated by the American Heart Association in Circulation 6
Chronic thromboembolic pulmonary hypertension develops in approximately 3.8% of patients within 2 years after an initial pulmonary embolism episode, with risk factors including delayed treatment and location of embolism, according to the American Heart Association in Circulation 6

Mistaking pulmonary hypertension for systemic hypertension, as stated by the American Heart Association in Circulation 6
Overlooking that arterial hypertension is actually a risk factor for developing pulmonary embolism rather than a consequence of it, as reported by the European Respiratory Society and the European Heart Society 1, 5

Acute pulmonary embolism interferes with both circulation and gas exchange, with right ventricular failure due to acute pressure overload being the primary cause of death in severe cases, as noted by the European Respiratory Journal and European Heart Journal 7, 8
The desynchronization of the ventricles may be exacerbated by the development of right bundle branch block, which can affect the cardiac conduction system, according to the European Respiratory Journal and European Heart Journal 7, 8
Excessive neurohumoral activation in pulmonary embolism can result from both abnormal right ventricular wall tension and circulatory shock, potentially affecting heart rate and rhythm, as reported by the European Heart Journal 8
Myocardial ischemia affecting the conduction system due to imbalance between oxygen supply and demand can contribute to bradycardia in pulmonary embolism, as noted by the European Heart Journal 8
Inflammatory response in the right ventricular myocardium can affect electrical conduction, as reported by the European Heart Journal 8

The European Society of Cardiology notes that pulmonary embolism can lead to right bundle branch block, which may be part of a broader effect on the cardiac conduction system, as reported by the European Respiratory Journal and European Heart Journal 7, 8
Bradycardia and AV block should raise suspicion for pulmonary embolism, especially when they occur suddenly in a patient with risk factors for venous thromboembolism, as noted by the European Respiratory Journal and European Heart Journal 7, 9

Patients presenting with new-onset bradycardia or AV block of unclear etiology should be evaluated for possible pulmonary embolism, especially if they have risk factors for venous thromboembolism, as reported by the European Respiratory Journal 7