Transradial Access Feasible, Beneficial in Cardiogenic Shock Patients

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Although patients with cardiogenic shock remain the ‘final frontier’ for even experienced operators well-versed in percutaneous coronary intervention (PCI) via the transradial route, such procedures can still lead to lower mortality and less bleeding in this extremely high-risk population, especially when performed at centers with high radial volume. Results from a large British registry study were published online March 31, 2014, ahead of print in the American Heart Journal.

Researchers led by Mamas A. Mamas, BM BCh, DPhil, of Manchester Royal Infirmary (Manchester, United Kingdom), looked at 8,222 patients with cardiogenic shock who received PCI between 2006 and 2012 while enrolled in the British Cardiovascular Intervention database. Transfemoral access was used in 74% of procedures and transradial in 26%.

Over the study period, prevalence of transradial access increased from 9.5% of all cardiogenic shock cases to 34.2% (P value for trend < 0.0001). There was a relationship between use of transradial access for shock and center experience. Only 37.1% of cardiogenic shock cases—whether transradial or transfemoral—were treated at centers that used transradial access more than 50% of the time. Almost two-thirds (62.4%) of those treated via transradial access were performed at these centers.

The overall rate of mortality at 30 days was 36.3% with a lower rate found in the transradial group. The same advantage with radial access was found for in-hospital MACCE (myocardial reinfarction, TVR, and cerebrovascular events) and major bleeding (table 1).

Table 1. Outcomes by Access Route in Patients with Cardiogenic Shock

On multivariable analysis, transradial access was associated with a lower risk of death at 30 day s in a propensity-matched cohort (HR 0.64; 95% CI 0.54-0.74; P < 0.001). Again, the same was true for transradial PCI and in-hospital MACCE (HR 0.64; 95% CI 0.53-0.76; P < 0.001) and major bleeding complications (HR 0.37; 95% CI 0.18-0.73; P = 0.004).

For 30-day mortality, there was no prognostic benefit associated with transradial PCI if performed at a center with the lowest percentage (0-25%) of transradial cases (HR 0.68; 95% CI 0.45-1.03; P = 0.06). However, radial access was independently associated with lower 30-day mortality at centers with greater use of the approach:

• 26-50% of cases: HR 0.64; 95% CI 0.48-0.87; P = 0.004
• 51-75% of cases: HR 0.66; 95% CI 0.48-0.90; P = 0.008
• 75% of cases: HR 0.50; 95% CI 0.35-0.73; P < 0.0001

Similar trends applied to center proportion of radial cases and in-hospital MACCE and major bleeding complications.

Bias May Have Skewed Results

The study authors caution, however, that there may be some selection bias affecting the results.

“Our data suggest that [transfemoral access] is utilized in more clinically unstable patients, which may in part contribute to the increased rates of mortality associated with [transfemoral access],” Dr. Mamas and colleagues note.

On the other hand, they say, a decrease in major bleeding with transradial access may have carried a survival benefit. “We show that utilization of [transradial access] is independently associated with a 63% lower risk of major bleeding complications in this high-risk cohort,” the investigators write, concluding that the current study “shows that whilst the majority of PCI cases performed in patients with cardiogenic shock in the [United Kingdom] are performed through [transfemoral access], the radial artery represents an alternative viable access site in this high-risk cohort of patients in experienced centers.”

R. Lee Jobe, MD, of Wake Heart and Vascular (Raleigh, NC), agreed with the study authors that transradial access in cardiogenic shock patients is viewed by many as “the last frontier.”

“It’s probably the last realm where people don’t want to go transradially because they feel like they need to get access as quickly and surely as possible,” he told TCTMD in a telephone interview. “And if hemodynamic support such as an Impella catheter or [intra-aortic] balloon pump needs to be used, many feel like having transfemoral access is a better way to make that happen. Plus, when someone is in cardiogenic shock, their radial pulse may not be that palpable, and it’s a little easier to blindly stick a femoral artery than a radial artery.”

Experience Key Factor

The good results of the paper with transradial access in cardiogenic shock patients demonstrate, Dr. Jobe stressed, that experience is key.

“What this shows is once operators become comfortable with the transradial approach, then they’re probably continuing to extend the mortality benefit that transradial imparts on their patients, even in cardiogenic shock patients,” he said. “I use the transradial approach for my cardiogenic shock patients because it leaves the groin available for an Impella, for a balloon pump, for temporary pace makers, for whatever need be. It helps because the catheters aren’t lying next to each other in the aorta. One of them is coming from the transradial down the ascending aorta and the other is coming up from the femoral through the descending aorta.”

According to Dr. Jobe, the benefits to cardiogenic shock patients seen with transradial PCI should apply to US practice if operators here gain similar experience. “What this tells us is once US operators become experienced, they should very strongly consider transradial even in their cardiogenic shock patients,” he said. “We’re not hurting them, and we’re probably helping them.”

Nevertheless, a “final frontier” remains for Dr. Jobe, a situation where he would still hesitate to use transradial access.

“The one patient for whom I still go to a femoral approach will be one with acute MI and cardiogenic shock with known previous bypass grafts,” he said. “That’s the kind of person I’m probably still going to go femoral if I’m not absolutely certain where all their bypass conduits come off because sometimes finding bypass conduits can be time consuming and challenging.”

Study Details

Clinical features were similar in the transfemoral and transradial groups, although transfemoral patients were more likely to have diabetes, be female, receive an intra-aortic balloon pump and inotropic support, or be ventilated. In general, patients treated with a transfemoral approach were sicker.

:

Mamas MA, Anderson SG, Ratib K, et al. Arterial access site utilization in cardiogenic shock in the United Kingdom; is radial access feasible? Am Heart J. 2014;Epub ahead of print.

Disclosures:

• Drs. Mamas and Jobe report no relevant conflicts of interest.

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