100 Cases in Clinical Medicine

(Rick Simeone) #1

ANSWER 51


This 62-year-old man had an anteroseptal myocardial infarctionindicated by Q-waves
in V2 and V3 and raised ST segments in V2, V3, V4 and V5. He became unwell suddenly
4 days later having had no initial problems. The late inspiratory crackles are typical of
pulmonary oedema and the chest X-ray confirms this showing hilar flare with some alveo-
lar filling, Kerley B lines at the lung bases and blunting of the costophrenic angles with
small pleural effusions.


The problems likely to occur at this time and produce shortness of breath are a further
myocardial infarction, arrhythmias, rupture of the chordae tendinae of the mitral valve, per-
foration of the intraventricular septum or even the free wall of the ventricle, and pulmonary
emboli. The first four of these could produce pulmonary oedema and a raised jugular venous
pressure as in this man. Pulmonary embolism would be compatible with a raised jugular
venous pressure but not the findings of pulmonary oedema on examination and X-ray.


Acute mitral regurgitation from chordal rupture and ischaemic perforation of the inter-
ventricular septum both produce a loud pansystolic murmur. The site of maximum inten-
sity of the murmur may differ being apical with chordal rupture and at the lower left
sternal edge with ventricular septal defect, but this differentiation may not be possible
with a loud murmur. The differentiation can be made by echocardiography.


The management of acute ventricular septal defect or chordal rupture would be similar and
should involve consultation with the cardiac surgeons. When these lesions produce haemo-
dynamic problems, as in this case, surgical repair is needed, either acutely if the problem is
very severe, or after stabilization with antifailure treatment or even counterpulsation with an
aortic balloon pump. Milder degrees of failure with a pansystolic murmur may occur when
there is ischaemia of the papillary muscles of the mitral valve. This is managed with anti-
failure treatment, not surgical intervention, and can be differentiated by echocardiography.



  • The cause of breathlessness after myocardial infarction needs careful evaluation.

  • The signs of ischaemic ventricular septal defect and mitral regurgitation due to chordal
    rupture after myocardial infarction may be very difficult to differentiate.

  • Patients with angina or myocardial infarction can also present with the radiating pain
    but no central chest pain, or with only the cardiac effects and no pain at all.


KEY POINTS

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