Invasive hemodynamic tracing in a patient with HCM showing inducible LVOT obstruction following a VPB and the Valsalva maneuver

Shown are five surface ECG leads (I, II, aVL, V1, V6) and the left ventricular (LV, arrows) and aortic (Ao, arrows) pressure tracings from a patient with hypertrophic cardiomyopathy. In the basal state, the LV and Ao pressures are equal at over 200 mmHg and there is no LV outflow gradient. However, after ventricular premature beats (VPB, arrows), there is an LV outflow tract pressure gradient of about 140 mmHg; in addition, the LV outflow tract pressure gradient is 70 mmHg during a Valsalva maneuver. LV outflow obstruction is associated with narrowing of the arterial pulse pressure.