Cangrelor Improves Heart Function in Cardiogenic Shock Patients
For heart attack patients who develop cardiogenic shock, an intravenous blood thinner called cangrelor results in better recovery of heart function than oral antiplatelet therapy, according to a study published in The Lancet.
Key Clinical Takeaways:
- Cangrelor achieved a 100 percent success rate in meeting the benchmark for effective platelet inhibition, compared to 22 percent for crushed ticagrelor.
- Patients treated with cangrelor experienced a 73 percent lower chance of developing microvascular obstruction.
- Left ventricular ejection fraction improvements at one year reached 37.9 percent via ultrasound for the cangrelor group, versus 21.7 percent for oral ticagrelor.
Cardiogenic shock represents the most serious complication of an acute myocardial infarction. Survivors face a higher risk of developing heart failure. Researchers conducted the DAPT-SHOCK-AMI trial to evaluate antiplatelet strategies in this high-risk population.
The randomized, double-blind study enrolled 605 patients who underwent cardiac stent procedures. Prior to intervention, researchers administered cangrelor to 298 participants and crushed ticagrelor, an oral antiplatelet medication, to 307 participants. The trial is the first randomized trial of double antiplatelet therapy in heart attacks complicated by cardiogenic shock and the largest randomized trial of antiplatelet strategies in cardiogenic shock to date.
Investigators analyzed the primary laboratory endpoint of a platelet reactivity index below 50 percent in a subset of 56 patients in the cangrelor group and 68 patients in the ticagrelor group. This benchmark for effective blood thinning was achieved in every patient receiving cangrelor, compared to only 22 percent of those receiving ticagrelor.
An imaging substudy revealed distinct differences in myocardial protection. Cangrelor was much better at protecting the heart against microvascular obstruction, a damaging phenomenon where plaque fragments or small clots plug small blood vessels in the heart muscle. Patients receiving the intravenous therapy showed a 73 percent reduction in this complication.
| Endpoint Measure | Cangrelor Group | Ticagrelor Group |
|---|---|---|
| Platelet Reactivity <50% | 100% | 22% |
| Microvascular Obstruction Reduction | 73% lower risk | Baseline |
| Ejection Fraction Gain (Ultrasound) | 37.9% improvement | 21.7% improvement |
| Ejection Fraction Gain (MRI) | 15.8% increase | 2.1% increase |
One-year follow-up imaging demonstrated substantial divergence in left ventricular ejection fraction recovery between the two cohorts. Ultrasounds showed a 37.9 percent improvement in the cangrelor group, compared to 21.7 percent in the ticagrelor group. Cardiac magnetic resonance imaging confirmed these findings, showing a 15.8 percent increase for cangrelor patients versus 2.1 percent for those on ticagrelor.
Beyond the findings regarding cangrelor, this trial establishes the value of serial echocardiography and MRI in characterizing recovery from cardiogenic shock, one of the most lethal conditions in medicine,
says Dr. Bhatt, describing the imaging substudy results. Cardiogenic shock carries a one-year mortality rate of approximately 50 percent.
Prior to these findings, prompt revascularization and mechanical heart pumps remained the only clinically validated interventions for cardiogenic shock. This is the largest randomized trial of antiplatelet strategies in cardiogenic shock to date. Our findings should help inform the design of future trials in this difficult-to-study population,
Dr. Bhatt states.
Researchers continue to follow the DAPT-SHOCK-AMI cohort to clarify the extended prognosis of survivors. Future research will likely utilize serial cardiac imaging protocols established in this trial to evaluate novel therapies for cardiogenic shock.
Disclaimer: The information provided in this article is for educational and scientific communication purposes only and does not constitute medical advice. Always consult with a qualified healthcare provider regarding any medical condition, diagnosis, or treatment plan.