VELOCITY: Hypothermia for STEMI Results in More Adverse Events, No Reductions in Infarct Size
Peritoneal hypothermia is feasible but also is associated with a high rate of adverse events in patients with STEMI without reducing infarct size, according to data from the prospective, randomized VELOCITY trial presented at TCT 2014.
TCT Course Director Gregg W. Stone, MD, of Columbia University Medical Center, New York, and colleagues aimed to assess the feasibility, safety and efficacy of systemic hypothermia induced by peritoneal lavage before primary PCI. STEMI patients from seven centers in the United States and Canada were assigned to undergo cardiac catheterization and PCI with (n=28) or without (n=26) hypothermia.
Successful hypothermia was initiated in 96.3% of patients in the intervention group. Median door-to-balloon time was 62 minutes in the hypothermia group and 47 minutes for controls (P=.007).
At 30 days, clinical events including the primary composite safety endpoint (death, reinfarction, ischemia-driven target vessel revascularization, major bleeding, sepsis, pneumonia, peritonitis, severe arrhythmia or renal failure), MACE and stent thrombosis occurred only in patients treated with the hypothermia protocol (see Figure).
Additionally, infarct size assessed by cardiac MRI after 3 to 5 days — the primary efficacy endpoint — was not reduced (17.2% in the hypothermia group vs. 16.1% in the control group; P=.54), and no significant differences were reported for target vessel and TIMI flow outcomes. “The results were pretty typical of what we have come to expect in terms of TIMI flow,” Stone said.
“Controlled systemic hypothermia through automated peritoneal lavage may be rapidly established in patients with evolving STEMI undergoing primary PCI at the expense of a modest increase in door-to-balloon time,” he added.
In the intervention group, an automated system was used (Velomedix) that lavaged the peritoneal cavity with 2.5 to 4.5 liters of lactated Ringer’s solution and hypothermia was induced to a target temperature of 34.9°C before PCI. The cavity was then cooled to a target temperature of 32.5°C, which was maintained for 3 hours after the procedure. Rewarming of the cavity was then initiated, followed by fluid drainage.
- Stone reports receiving consultant fees/honoraria from TherOx and Velomedix.