The Role of Echocardiography in the Assessment of Ventricular Septal Rupture Postmyocardial Infarction

Abstract

Ventricular septal rupture (VSR) is a rare life-threatening mechanical complication secondary to acute myocardial infarction that usually occurs 2 to 8 days after infarction and frequently precipitates cardiogenic shock. The mortality rate for VSR has been reported to be between 41% and 80%; therefore, immediate surgical intervention should be considered. Furthermore, VSR is a complication of 0.17% to 0.31% of patients who present with an anterior myocardial infarction. Because of the rarity of this pathology, the role of transthoracic echocardiographic investigation will help to improve what is already considered a poor prognosis for these types of patients. This case study illustrates how transthoracic echocardiography plays an essential role in the rapid assessment and diagnosis of VSR in clinical practice.

Case of ventricular septal rupture following acute myocardial infarction

“…Due to the high specificity and sensitivity of ultrasound in the detection of a VSR, bedside echocardiography is often the front-line imaging technique utilised in these patients. 1 , 6 An important aspect of the echocardiographic assessment of a patient with a suspected VSR is the need to evaluate the ventricular septum from multiple imaging windows including non-standard or off-axis imaging planes. 1 , 3 , 6 The VSR will appear on 2D imaging as an area of discontinuity or ‘drop-out’ in the ventricular myocardium.…”

“…1 , 6 An important aspect of the echocardiographic assessment of a patient with a suspected VSR is the need to evaluate the ventricular septum from multiple imaging windows including non-standard or off-axis imaging planes. 1 , 3 , 6 The VSR will appear on 2D imaging as an area of discontinuity or ‘drop-out’ in the ventricular myocardium. The anatomical size of the shunt can be estimated using 2D calipers to measure from one border of the defect to the other border.…”

“…3 The presence of an apical aneurysm increases the risk of septal rupture, thus apical aneurysms in patients with a new systolic murmur post anterior MI should be thoroughly evaluated for the presence of a VSR. 3,6…”

“…In addition, the blood velocity information obtained with CW Doppler can be used to estimate the severity of shunting using the Qp:Qs shunt calculation. 6 A normal shunt ratio is 1:1 which indicates no direct communication between the systemic and pulmonary circulations and that blood volume in each of the circulations is equivalent. 6 VSR closure is indicated when the Qp:Qs is greater than 1.5 and there is presence of LV systolic or diastolic dysfunction or cardiac failure.…”

“…6 A normal shunt ratio is 1:1 which indicates no direct communication between the systemic and pulmonary circulations and that blood volume in each of the circulations is equivalent. 6 VSR closure is indicated when the Qp:Qs is greater than 1.5 and there is presence of LV systolic or diastolic dysfunction or cardiac failure. 9 The Qp:Qs in this patient was 1.7 which supported the need for surgical intervention to reduce the risk of deterioration into cardiac failure.…”