Commentary:
This paper holds a rather exclusive position in the domain of cardiac
surgery; representing a rare, lethal, and mortal condition in a large
number, 1010 cases, and spanning over 23 years, representing a single
population. Ventricular septal rupture (VSR) is known to cause extensive
damage to the myocardium with shunting across the ventricular chambers
rendering volume overload. In the EuroScore II, risk assessment scale
for cardiac surgery, VSR holds the maximum score on the scale (1).
Although excellent early reperfusion strategies for the myocardium
following myocardial infarction (MI), have decreased the occurrence of
VSR, the overall surgical mortality due to VSR reported in this paper is
38.9%. Ventricular septal rupture is seen in the first week following
MI. Myocardium differs from the rest of the tissues owing to the
potential ”limited blood supply to the damaged myocardium for healing
due to narrowing of coronary arteries and the myocardium, which must
continue to function during the process of repair, whereas other tissues
can be immobilized”. Most of the patients are elderly with hypertension
leading to increased afterload to the left ventricle (LV), furthermore
leading to stress at the junction of the healthy and infracted tissues,
which allows the paradoxical systolic movement leading to the rupture of
the necrosed myocardium(2).
In the study, the data collected by the authors, indicate that early
surgery in cases with VSR leads to mortality(1 to 30 days Vs
>30 days: Odds ratio of 0.35 Vs 0.25) owing to technical
difficulties, more fragile tissues, which leads to the suture to cut
through the necrosed myocardium, should be operated as late as possible
if hemodynamics permit.
The authors also highlight the importance of concomitant coronary artery
bypass grafting (CABG)(p=0.544) and Mitral Valve Repair (p=0.524)
alongside VSR repair, adding that no additional risk was being imparted
and it could prove to be beneficial to revascularize the weak myocardium
in long run.
The study also mentions the role of percutaneous closure to bail out the
crisis, pros & cons, indications, success rate (90%), and mortality.
In 1957, Denton Cooley first succeeded in surgical repair of VSR but
unfortunately, the patient died 6 weeks later. The first successful
long-term survivor was operated by Spencer Payne in 1960 by opening the
right ventricular outflow tract (RVOT). The patient was asymptomatic 2 ½
yrs after surgery when followed up regularly (3). Early surgical repair
of VSR following MI has drawbacks of its own, for example, suture cut
through necrosed tissue. Via different approaches also, either through
RV or LV, via direct suture closure, prosthetic closure, or percutaneous
closure, outcomes are not satisfactory. Despite understanding the
pathophysiology, early diagnosis, and revascularization, advances of
cardiopulmonary bypass techniques and mechanical circulatory support
like Intra Aortic Balloon Pump (IABP), ventricular assist devices,
outcomes are dismal owing to the loss of functional myocardial reserve.
A tailor can design the garment in the desired fashion, but can’t change
the quality of cloth, the same analogy is applied to the surgeon as
well, till the quality of the myocardium is good.