Jan 05 2024 This Week in Cardiology

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In This Week’s Podcast

For the week ending January 5, 2024, John Mandrola, MD, comments on the following news and features stories: Neuro-modulation in HF, private equity as hospital owners, HCM, SCD and ICD re-evaluated, and peer review.

Barostimulation for HF

About a year ago, a vascular surgeon friend asked me what I thought of this carotid stimulation device. I’m like, a) why are you asking, and b) what are you talking about?

Apparently, our hospital system was considering doing barostimulation and it required a vascular surgeon. He told me he had looked at the study, and it’s not that impressive.

At the time I briefly looked at the BEAT HF study, and thought not much here, but, I paid it little attention. Mainly because this therapy didn’t have much traction.

Well, over the holidays, the FDA approved an expanded label for the Barostim neuromodulation system in patients with heart failure (HF) that incorporates longer-term, postmarketing clinical data from the BeAT-HF randomized clinical trial, the manufacturer, CVRx Inc, has announced.

The updated labeling for Barostim now states that the device is indicated for patients with NYHA class III or class II HF with a recent history of class III disease despite treatment with guideline directed medical therapy (GDMT), and who have a left ventricular ejection fraction (LVEF) ≤ 35% and an N-terminal pro B-type natriuretic peptide level < 1600 pg/mL.

I did not really know there was ANY indication. Now we have an expansion of an indication.

The grand idea is that there are groups of patients with HF with reduced EF (HFrEF) who still have symptoms and bad LVEF, despite medical therapy. And sadly, their QRS duration precludes benefit from cardiac resynchronization therapy (CRT).

This is the patient who might improve with modulation of the autonomic nervous system.

A company called CVRx came up with a subcutaneously implanted device, placed in the upper chest. A lead is tunneled from the carotid bulb area to the device which delivers stimulation to the carotid area with the goal of decreasing sympathetic tone (like beta-blockade). Basically, it counters the excessive sympathetic tone in HF.

The company and academics worked with FDA to design an adaptive trial. The main publication, (that I could find) is JACC 2020, first author, Michael Zile.

BEAT HF had four cohorts. Some designed for pre-market approval.

Each cohort was a small randomized controlled trial (RCT) comparing one group with the device and the other with medical therapy.

The main publication focuses on the last cohort of 260 patients randomized 1-1 to BAT+ medical therapy vs medical therapy. This so-called cohort D was the “intended use” indication.

The primary endpoint was a composite of three things—quality of life (QOL) scores, 6 min walk, and NT-pro-BNP.

At 6 months, the BAT group had better QOL, longer 6 min walk tests and slightly better NT-proBNP. All were statistically significant.

But I hope you all note the limitations. A) this is a surgical procedure that requires indwelling hardware and a vascular surgeon. B) there were no clinical outcomes, such as hospitalization for HF (HHF) or CV death, and C) and this is huge: there was no placebo or sham procedure. Patients in the device arm knew they had had surgery and patients in the medical arm knew that they did not.

What are people thinking? Of course, there will be a placebo effect. The authors tell us the lack of placebo is why they used NT-proBNP, an objective measure. But come on, BP is an objective measure and look what happened with the early renal denervation trials.

Patients who had surgery may have done other things that helped lower their BNP—better diet, more exercise, better adherence to meds, etc.

I had no idea how weak the evidentiary data for barostimulation was. And then reading that the FDA expanded the indication last month stimulated me to look harder.

I found that Zile presented longer term data from BEAT HF looking at clinical outcomes in March 2023 at the technology and HF therapeutics conference (THT). There was no improvement in the composite of CVD and HF events.

We refer most of our advanced HF patients to transplant centers. We don’t use this device. I’ve never seen a patient with one.

But it is FDA approved. With uncontrolled data and no clinical outcome data. How could this be? I am not against innovation.

But why would there not be a proper placebo-controlled trial? Or one powered for clinical endpoints?

If you are a HF person and know of stronger data, please alert me and I will update this critical appraisal.

Private Equity Owned Hospitals

JAMA published a study looking at changes in hospital adverse events and patient outcomes associated with private equity acquisition.

I am not sure what’s happening outside of the US, but here, many hospitals are being acquired by private equity groups.

From the paper: “private equity has an often-distinct business model, in which the acquired entity typically assumes debt in the initial acquisition and is sold within a short time frame (often within 3-7 years).”

When I asked ChatGPT what do private equity firms seek to gain when acquiring hospitals, it said there can be many goals, but first listed profitability and financial returns.

I get the sense that profit in the healthcare sector is baddy. Indeed, the Biden administration is scrutinizing these takeovers.

The Bayesian priors before an observational study looking at outcomes after takeovers, may be that the health scientists expect to find worse outcomes. Because profit in healthcare is bad.

Here’s a brief summary of the study.

Harvard authors used Medicare claims data (adults > 65) to study outcomes at 52 private equity acquired hospitals vs 259 matched control hospitals over a decade. This was more than 4 million hospitalizations.

So this was a non-random comparison study looking back at claims data.

The main outcome measures were adverse events in the hospital—falls, infections. They also looked at mortality discharge disposition and readmissions.

You can guess the results. Profit motive in hospital care is BAD. The authors found a roughly 25% increase in hospital acquired conditions at acquired hospitals vs controls. This was driven by a 27% increase in falls, 37% increase in central line infections, and a doubling of surgical site infections.

And the news coverage was all bad. Headlines related bad outcomes after profiteers take over.

I am no fan of excessive profiteering in the care of people who are asking for our help. But I also think the use of dubious evidence to advance an idea is bad.

First, the relative increase of 25% sounds terrible. But the absolute increase in say falls, was equal to an extra 2 falls per 10,000 admissions. In fact, all of the adverse outcomes were measured in per 10,000 admissions. An extra 2 falls per 10,000 admissions. I am sorry, that may be statistically significant, but 9,998 other patient admissions had no difference.

Lesson number 1 – studies with millions of patients can have tiny differences that reach statistical significance.

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