Summary of Ray’s case presentation on 4 Dec:
Obese 55 year man presents after a sudden collapse at home, with new-onset rapid AF and profound, hypotensive shock. His illness seemed to have a very short time-course.
Initial DDx for shock?
– Big AMI with severe LV dysfunction
– AMI with papillary muscle rupture leading to acute mitral regurgitation
– Primary Arrhythmia – unstable rapid AF
– Massive PE
– Tension pneumothorax
– Septic shock
– Intraabdominal ?AAA
On initial assessment, he was desperately unstable. ECG showed AF (rate 160-200) and RBBB. CXR, VBG were non-specific.
Emergent cardioversion (with minimal, very nerve-racking, sedation) produced sinus tachycardia, but hypotension and peripheral circulatory failure persisted.
Investigation of choice?
Bedside echo showed a very dilated, hypokinetic RV, and followup formal study confirmed this, along with normal LV function. There was no pericardial effusion.
By this time, the patient was stabilised, on a central noradrenaline infusion at 3mcg/min. He looked much better.
CTPA was ordered and showed large, bilateral proximal and saddle PEs.
Now that the diagnosis of massive PE was confirmed, thrombolysis was considered. But in a now-stable patient, does the benefit outweigh the risks of bleeding with ‘lysis?
The following document provides some suggestions and makes good reading: Euro PE Guidelines 2008
Here’s the summary, for thrombolysis in PE:
Guideline-recommended for “massive” PE, defined as:
– cardiac arrest,
– shock, or
– a drop in SBP to ≤ 90 mmHg for at least 15 minutes.
How to do it:
Several trials show improvements in cardiac index, pulmonary arterial pressure, echo signs of RV dysfunction in the short term (ie. a few hours).
However, these haemodynamic benefits from thrombolysis, although rapid in onset, are confined to the first few days, and at 7 days are equal to just giving heparin.
Clinical benefits are poorly studied:
If you have made the diagnosis, and the patient is shocked or in cardiac arrest, give the ‘lysis. In Ray’s case, the diagnosis was confirmed only after resuscitation and supportive care had stabilised the patient, at which point the risk:benefit balance was less certain. In the end, the patient was heparinised, weaned off norad in a few hours and did well. Without thrombolysis.
NB: The above 2008 guidelines were published before the recent MOPPET trial, which concluded that in patients with submassive PE, “half-dose” thrombolysis was safe, and led to improved haemodynamic outcome (risk of pulmonary hypertension) at 28 months.