Hemodynamic Signatures in Cardiac Pathologies

Mitral Stenosis

The Wiggers diagram demonstrates a prolonged left‑atrial to left‑ventricular pressure gradient during diastole, with persistently elevated left‑atrial pressure and a slow decline of the left‑atrial pressure curve. 1
Left‑atrial pressure remains elevated with a prominent a‑wave due to forceful atrial contraction against the stenotic mitral valve (when sinus rhythm is present). 1
The y‑descent (early diastolic emptying of the left atrium) is slow and gradual because flow through the narrowed valve orifice is restricted. 1
Left‑ventricular end‑diastolic pressure may be normal or low, maintaining a persistent diastolic pressure gradient across the mitral valve. 1

A characteristic systolic pressure gradient develops between the left ventricle and the aorta, accompanied by a delayed and reduced aortic pressure upstroke (pulsus parvus et tardus). 6
Left‑ventricular systolic pressure is markedly elevated while aortic systolic pressure is reduced, producing a large systolic gradient. 1
The aortic pressure waveform shows a slow upstroke and reduced pulse pressure. 1
Left‑ventricular end‑diastolic pressure is often elevated owing to concentric hypertrophy and diastolic dysfunction. 5
The left‑atrial pressure tracing exhibits a prominent a‑wave, reflecting forceful atrial contraction needed to fill the hypertrophied, stiff left ventricle. 1
Ejection time is prolonged and aortic‑valve closure is delayed. 1

The aortic pressure curve displays a wide pulse pressure with rapid rise and fall (Corrigan pulse), and left‑ventricular end‑diastolic pressure may equal or exceed left‑atrial pressure. 1
Aortic diastolic pressure falls rapidly to very low levels because of regurgitant flow back into the left ventricle. 1
Left‑ventricular end‑diastolic pressure is elevated and can approach left‑atrial pressure, potentially causing premature mitral‑valve closure. 1
Left‑ventricular systolic pressure is increased due to the large combined forward and regurgitant stroke volume. 5
The left‑ventricular pressure curve shows a rapid early‑diastolic pressure rise as regurgitant blood fills the ventricle. 1
In chronic severe aortic regurgitation, left‑ventricular end‑diastolic and end‑systolic volumes are markedly increased (eccentric hypertrophy). 5

The right‑atrial pressure tracing shows loss of the normal x‑descent (obliterated or reversed) in severe tricuspid regurgitation. 2
Right‑ventricular systolic pressure may be normal or elevated depending on the presence of pulmonary hypertension. 2
The inferior vena cava is dilated with minimal respiratory collapse, reflecting elevated right‑atrial pressure. 1

Diastolic pressures become equalized across all cardiac chambers, and ventricular pressure tracings exhibit a “square‑root” dip‑and‑plateau (square‑root sign) pattern. 1
Ventricular diastolic pressure shows rapid early filling (steep y‑descent) followed by an abrupt plateau as the rigid pericardium limits further filling. 1
Right‑ and left‑ventricular end‑diastolic pressures are elevated and typically within 5 mm Hg of each other. 1
Right‑atrial pressure displays prominent x‑ and y‑descents, producing an “M” or “W” configuration. 1
Atrial pressures remain elevated throughout the cardiac cycle with minimal variation. 1
Ventricular interdependence is present, with reciprocal changes in right‑ and left‑ventricular filling during respiration. 1

Elevation and equalization of diastolic pressures occur in all chambers, with loss of the normal y‑descent in atrial pressure tracings. 1
Right‑atrial pressure is elevated with a prominent x‑descent but an absent or blunted y‑descent because pericardial pressure prevents normal early diastolic ventricular filling. 1
All cardiac‑chamber diastolic pressures are elevated and equalized within approximately 5 mm Hg. 1
The right‑atrial pressure curve shows only a single descent per cardiac cycle (the x‑descent). 1
Pulsus paradoxus is present, defined by an inspiratory fall in systolic blood pressure greater than 10 mm Hg. 1
Ventricular filling is restricted throughout diastole, contrasting with the rapid early filling seen in constrictive pericarditis. 1

Left‑ventricular end‑diastolic pressure is markedly elevated (often >20 mm Hg), reflecting impaired diastolic compliance and/or systolic dysfunction. 1
Left‑atrial pressure is elevated throughout the cardiac cycle with prominent a‑ and v‑waves. 1
Pulmonary‑artery systolic pressure is elevated (often >50 mm Hg) together with an increased pulmonary‑capillary wedge pressure, indicating backward transmission of left‑atrial pressure. 1
Left‑ventricular systolic pressure may be normal or reduced depending on the severity of contractile dysfunction. 1
The left‑ventricular pressure‑volume loop is shifted rightward and upward, showing increased end‑diastolic and end‑systolic volumes. 5

Pressure gradients must be measured simultaneously; sequential measurements can be misleading, especially in conditions with beat‑to‑beat variability. 1
In aortic stenosis with a low gradient and reduced ejection fraction, dobutamine stress echocardiography should be performed to differentiate true severe stenosis from pseudo‑stenosis. 1