Hi readers
You may have seen this question recently :
A 60 year old Asian man with a history of type 2 diabetes on insulin and hypertension presents with deteriorating renal function and is referred by his GP to the renal clinic. In the renal clinic, he is found to have leg oedema, elevated JVP with rapid x-descent, ascites, mild jaundice and bi-basal dullness. Chest X-ray shows cardiomegaly. ECG shows left ventricular hypertrophy with strain. Resting heart rate was 100 bpm and BP of 90/70. The definitive cardiac diagnosis can be obtained by -
a. Cardiac MRI
b. CT pulmonary angiography
c. Ventilation-perfusion scan
d. Transthoracic Echocardiography
e. Right and left heart catheterisation
In the patient above, which of the following observation is likely to be true?
a. Absent contrast reflux into the hepatic vein on CTPA
b. Pulsus paradoxus of 30 mmHg on clinical examination
c. Paradoxical septal motion on transthoracic echocardiography
d. Myocardial speckling on CMR
e. Pulmonary capillary wedge pressure of 15mmHg on cardiac catheter
Here are the answers to the questions
Question 1 - d
Question 2 - b
Explanation
In the clinical scenario, the leg oedema, elevated JVP and ascites indicate high right ventricular pressures. Mild jaundice could be secondary to hepatic congestion and the bibasal dullness is likely due to pleural effusions. The rapid x-descent on JVP raises the suspicion of pericardial effusion, which is likely in this patient with renal failure. Hence option D is the investigation of choice.
Gadolinium contrast should be used with caution for cardiac MRI in the presence of significant renal impairment, so is not indicated in this patient. The clinical history makes acute pulmonary embolism unlikely, and hence CTPA and V/Q scan are not indicated. Right and left heart catheterisation is indicated in the absence of pericardial effusion, and aid in the diagnosis of restrictive cardiomyopathy of constrictive pericarditis.
Reflux of contrast into the hepatic vein on CTPA is indicative of tricusid regurgitation and high RV pressure. A pulsus paradoxus of 30 mmHg indicates cardiac tamponade which is likely in this patient with hypotension, tachycardia and clinical features of severe pericardial effusion. Paradoxical septal motion on transthoracic echo is indicative of pulmonary hypertension (which could be secondary to other causes). Myocardial speckling on CMR is seen in amyloidosis.
A PCWP of 15mmHg on cardiac catheter indicates minimally elevated left atrial pressure, which is unlikely to be the case in this patient. Therefore the answer to the second question is B.
Note : In patients with pulmonary hypertension and cardiac tamponade, the classic echo features of right atrial and right ventricular collapse may be delayed.
Our sincere thanks to Dr Ramachandra, senior registrar in interventional cardiology for his input.
New questions coming soon!!!
