Pulmonary regurgitation

Pulmonary regurgitation

Pulmonary regurgitation (PR) can be divided into hypertensive and non-hypertensive. The former is associated with pulmonary arterial hypertension while the latter is not.

Hypertensive pulmonary regurgitation

Hypertensive PR is associated with severe pulmonary hypertension. It produces a blowing, decrescendo early diastolic murmur with the eponym Graham Steell murmur [1]. The murmur is heard in the pulmonary area and left sternal border, resembling the murmur of aortic regurgitation. It may be heard in Eisenmenger syndrome, severe primary pulmonary hypertension and severe pulmonary hypertension secondary to left heart disease like severe mitral stenosis. The murmur starts early in diastole after the loud pulmonary component of the second heart sound. A mid diastolic and presystolic murmur known as right sided Austin Flint murmur [2,3] may sometimes be associated.

Non hypertensive PR

Pulmonary regurgitation can occur without pulmonary hypertension in:

1. Infective endocarditis – perforation and other types of damage
2. After repair tetralogy of Fallot, especially with a transannular patch
3. After surgical or percutaneous relief of pulmonary stenosis
4. Absent pulmonary valve – though usually associated with tetralogy of Fallot, can occur in isolation.
5. Carcinoid syndrome involving mainly the right sided valves
6. Rheumatic heart disease. Rheumatic fever can very rarely involve the pulmonary valve. Since the hemodynamic load is least on the pulmonary valve, involvement of pulmonary valve by the rheumatic process is least likely. Most often in rheumatic heart disease, PR is due to mitral stenosis and severe pulmonary hypertension (hypertensive PR).

The murmur of non hypertensive PR is of lower pitch and delayed diastolic, occurring a bit delayed (compared to the murmur of aortic regurgitation, which occurs after A2), after the pulmonary component of second heart sound [4].

Severe PR after repair of Tetralogy of Fallot may lead to right ventricular failure in the long run and need interventions. It can lead to right ventricular dysfunction, decreased exercise capacity, increased arrhythmias and risk of sudden cardiac death [5]. Pulmonary valve replacement if needed, should be done before irreversible right ventricular dysfunction sets in.

Eighty seven percent of surgically operated cases of pulmonary stenosis had PR on echocardiography of which 28% was more than moderate, as documented by the Second Natural History Study of Congenital Heart Defects [6]. It may be noted that surgical pulmonary valvotomy is seldom done these days. Surgical management is reserved for supra and sub valvular pulmonary stenosis. PR seems to be less common after balloon pulmonary valvotomy.

References

1. A G Fraser, C F Weston. The Graham Steell murmur: eponymous serendipity? J R Coll Physicians Lond. 1991 Jan;25(1):66-70.
2. T Kambe, N Hibi, Y Fukui, K Nishimura, S Ichimiya, M Toguchi, N Sakamoto. Clinical study on the right-sided Austin Flint murmur using intracardiac phonocardiography. Am Heart J. 1979 Dec;98(6):701-7.
3. Green EW, Agruss NS, Adolph RJ. Right-sided Austin Flint murmur. Documentation by intracardiac phonocardiography, echocardiography and postmortem findings. Am J Cardiol. 1973 Sep 7;32(3):370-4.
4. J C Holmes, N O Fowler, S Kaplan. Pulmonary valvular insufficiency. Am J Med. 1968 Jun;44(6):851-62.
5. Beatriz Bouzas 1, Philip J Kilner, Michael A Gatzoulis. Pulmonary regurgitation: not a benign lesion. Eur Heart J. 2005 Mar;26(5):433-9.
6. C J Hayes, W M Gersony, D J Driscoll, J F Keane, L Kidd, W M O’Fallon, D R Pieroni, R R Wolfe, W H Weidman. Second natural history study of congenital heart defects. Results of treatment of patients with pulmonary valvar stenosis. Circulation. 1993 Feb;87(2 Suppl):I28-37.