Venturi effect and heart

The Venturi effect is the reduction in fluid pressure that results when a fluid flows through a constricted section (or choke) of a pipe. The Venturi effect is named after Giovanni Battista Venturi (1746–1822), an Italian physicist.

The role of venturi effect has been liberally studied in cardiology.some conditions which noted to have a venturi effect on pathophysiology include:

In systolic anterior motion (SAM) of the mitral valve in hypertrophic cardiomyopathy venturi effect is thought to play a role.But in many cases SAM began prior to ejection in patients with hypertrophic cardiomyopathy doubting this theory.

Similarly dynamic obstruction to dobutamine can occur with stress echocardiography due to venturi effect.Dynamic obstruction related to dobutamine stress will show late-peaking doppler signal that exceeds the velocity at rest by at least 1 m/s or an absolute velocity of greater than 2.5 m/sec occur in both hypertrophied or normal thickness ventricles.

Rheolytic thrombectomy for thrombotic lesions in PCI involves use of a high-velocity jet of saline solution ejected to create a Venturi effect at the tip of a small catheter.

In aortic stenosis post TAVR venturi effect is being studied for disparity in velocities despite correction of gradients by TAVR

In ventricular septal defect prolapse of cusp can occur due to venturi effect of flow across VSD.Prolapse of NCC resulting in progressive AR is well known as a syndrome.Can you tell what is it?

see comment section for answer !


Pellikka, PA, Oh, JK, Bailey, KR, Nichols, BA, Monahan, KH, Tajik, AJ Dynamic intraventricular obstruction during dobutamine stress echocardiography: A new observation.. Circulation. (1992). 86 1429–32 [Article] [PubMed]

Roldan, FJ, Vargas-Barron, J, Espinola-Zavaleta, N, Keirns, C, Romero-Cardenas, A Severe dynamic obstruction of the left ventricular outflow tract induced by dobutamine.. Echocardiography. (2000). 17 37–40

Reversing constriction without surgery?

Pericardiectomy can be curative in constriction but some surgeons may hate it because of challenging and painstaking procedure .

A rare subset of patients with constrictive pericarditis are actually having an inflammatory transient constrictive pericarditis.

Late gadolinium enhancement of pericardium may suggest this condition and may respond to therapy leading to a “reversible” constrictive pericarditis

concertina effect

concertina is a free-reed musical instrument, It consists of expanding and contracting bellows, with buttons (or keys) usually on both ends, unlike accordion buttons, which are on the front.

Concertina effect is seen in medicine in which of following conditions? Choose the correct responses?

  1. Coronary angioplasty due to guidewire
  2. WPW syndrome
  3. Intestinal obstruction
  4. coronary angioplasty due to stent strut compression
  5. Right atrial pectinate muscle

see comment section for answer