Cardiology Digest podcast: Episode #11

Study #1

First, we explore an analysis that compares coronary CT angiography (CCTA) with stress modalities like SPECT-MPI. We see if CCTA has the potential to reduce the need for invasive angiography, and how it stacks up against other testing strategies.

"The key clinical outcomes they looked at included cardiovascular-related death, myocardial infarction, and the need for invasive procedures like coronary angiography and revascularizations after the initial diagnostic test."

Zito, A, Galli, M, Biondi-Zoccai, G, et al. 2023. Diagnostic strategies for the assessment of suspected stable coronary artery disease: A systematic review and meta-analysis. Ann Intern Med. 6: 817–826. (https://www.acpjournals.org/doi/10.7326/M23-0231)

Study #2

We discuss the approval of a dual-chamber leadless pacemaker system by the FDA. Although this study supports the efficacy of this innovative approach in certain scenarios, it also raises important concerns.

"For years, we’ve used leadless pacemakers, which are primarily ventricular single-chamber devices. Those devices include the Medtronic leadless pacemaker, which employs an accelerometer algorithm to detect atrial contractions. However, they fall short as they cannot pace the atrium."

Knops, RE, Reddy, VY, Ip, JE, et al. 2023. A dual-chamber leadless pacemaker. N Engl J Med. 25: 2360–2370. (https://www.nejm.org/doi/10.1056/NEJMoa2300080)

Study #3

Then we look at a comprehensive retrospective study that evaluates aggressive management of hypertension in hospitalized adults. What are the ramifications of minimizing the use of BP-lowering agents, particularly intravenous ones, in certain inpatient scenarios?

"They looked at patients who had two or more instances of high systolic blood pressure (above 140 mmHg) within the first 48 hours of admission. The 'aggressive management'  group received one or more oral or intravenous doses of antihypertensive medication that they weren’t taking before admission to hospital. Unfortunately, a troubling trend emerged."

Anderson, TS, Herzig, SJ, Jing, B, et al. 2023. Clinical outcomes of intensive inpatient blood pressure management in hospitalized older adults. JAMA Intern Med. 7: 715–723. (https://jamanetwork.com/journals/jamainternalmedicine/article-abstract/2805021)

Pacemaker Essentials (5 CME)

Pacemaker Essentials Workshop (1 CME) 

Coronary Angiography Essentials (3 CME) 

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Please note that these timestamps are auto-generated and may be approximate.

Nora [00:00:04]:

Hello, and welcome to Medmastery’s Cardiology Digest, where expert insights are unleashed. I’m Nora, and today my co-host Peter and I are digging into the results of three groundbreaking trials from top journals. If you’re a physician or other healthcare professional with an interest in cardiology, you’re going to love what we have in store for you today! First, we look at an analysis from the Annals of Internal Medicine that compares Coronary CT Angiography, or CCTA, with traditional stress testing modalities like SPECT-MPI, and we see if it can reduce the need for invasive angiography. Next, we discuss a paper from the New England Journal of Medicine addressing the recent FDA approval of a dual-chamber leadless pacemaker system, and we find out if this innovative approach will transform pacemaker therapy. Lastly, we turn our attention to a retrospective study in JAMA Internal Medicine that explores the aggressive management of hypertension in hospitalized adults. The findings raise important concerns about the use of blood pressure lowering agents, especially intravenous ones. Join us as we explore these intriguing topics. 

Nora [00:01:14]:

And as always, don’t forget to subscribe so you’re always up to date on the latest cardiology insights and breakthroughs. Now, Peter’s going to get us started with our first study.

Peter [00:01:25]:

Thanks for that intro Nora! We’re going to kick off today with a closer look assessing suspected stable coronary artery disease, and how different diagnostic approaches impact clinical outcomes. Published in the Annals of Internal Medicine in June 2023 by Zito and colleagues, this study is a systematic review and meta-analysis that synthesizes findings from 11 randomized, controlled trials. The key clinical outcomes they looked at included cardiovascular-related death, myocardial infarction, and the need for invasive procedures like coronary angiography and revascularizations after the initial diagnostic test. The first tests we’ll compare are coronary computed tomographic angiography (CCTA), single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI), and exercise electrocardiography. CCTA was associated with a lower risk of MI and CV-related death (the relative risk was approximately 0.65) when compared to exercise electrocardiography and SPECT-MPI. But, CCTA was linked to an increased need for initial revascularizations…

Peter [00:02:30]:

… (the relative risk was 1.78) when compared to exercise electrocardiography. Now let’s compare CCTA to a direct referral for angiography. The rates of MI and death related to cardiovascular disease were similar in both groups. But CCTA was associated with fewer angiograms (the relative risk was 0.23). CCTA was also associated with fewer index revascularizations (the relative risk was 0.71). So, what’s the main takeaway? CCTA is a less invasive diagnostic route for patients with suspected coronary artery disease that can reduce the need for invasive angiography and follow-up revascularizations. It's important to mention that each of the comparisons made was based on a limited subset of the available trials, which highlights the need for further research in this area. Experts commenting on the study noted that for certain cases CCTA has significant potential to serve as a gatekeeper for invasive angiography.

Peter [00:03:24]:

This analysis also draws attention to the interesting comparisons between CCTA and stress modalities like SPECT-MPI, which have historically shown similar clinical outcomes according to individual studies like PROMISE. However, the analysis also points to a limitation: the relative scarcity of randomized data for commonly used methods such as stress echocardiography. As we continue to navigate the complexities of heart health, studies like these are instrumental in improving patient outcomes and guiding clinical decisions. Speaking of decisions, now let’s see whether a new pacemaker design will be a better choice for our patients. Over to you Nora!

Nora [00:03:59]:

Thanks Peter! This study, spearheaded by Knops and colleagues and published in the New England Journal of Medicine in June 2023, shines a light on a significant advancement in pacemaker design, specifically, a dual-chamber leadless pacemaker. This is the first time such a design has ever been approved by the FDA. For years, we’ve used leadless pacemakers, which are primarily ventricular single-chamber devices. Those devices include the Medtronic leadless pacemaker, which employs an accelerometer algorithm to detect atrial contractions. However, they fall short as they cannot pace the atrium. Addressing this limitation, this manufacturer-sponsored, multicenter, prospective, single-group study introduces a dual-chamber leadless pacemaker system. The study enrolled 300 patients who received a right atrial pacemaker along with a separate right ventricular pacemaker.

Nora [00:04:52]:

In 295 patients (98.3%) the implantation was a success and communication between the two pacemakers was effectively established. At the three-month mark, 90% of patients achieved the primary performance endpoint of ≥70% atrioventricular synchrony. Also, 90% of patients were free from complications at three months (which was the study’s primary safety endpoint). However, it's important to note that 29 patients experienced 35 procedure- or device-related serious adverse events. This study confirms the functionality of the dual-chamber leadless pacemaker system. Yet, it's crucial to consider the expert commentary on this study. Concerns remain regarding the removal of these devices due to fibrosis and the limited space within the atrium and ventricle for implantation. This suggests that using such pacemakers in patients who are younger is probably best avoided. Despite these challenges, the dual-chamber leadless pacemaker system has potential to be a good solution for patients at a higher risk of infection from traditional transvenous devices…

Nora [00:06:01]:

…(for example, patients who have diabetes or are on dialysis). It also could be a good solution for patients who aren’t likely to require a replacement during their lifetime. As we reflect on this study, it's clear that the dual-chamber leadless pacemaker system is a landmark in the field of cardiology, offering new horizons for patient care and treatment efficacy. Now our next study brings us important info on the management of blood pressure in older adults during hospital stays and shows us the negative outcomes associated with certain practices that are still used in clinical practice today.

Nora [00:07:50]:

This study sheds new light on aggressive management of elevated blood pressure in older adults during hospital stays. It was published in July 2023 in JAMA Internal Medicine, and conducted by Anderson and colleagues. Their large-scale retrospective analysis looked at over 60,000 patients who were 65 years of age or older and admitted to hospital for conditions unrelated to cardiac issues. The researchers zeroed in on the impact of aggressively managing high systolic blood pressure in these patients. What did they mean by "aggressive management"? Well, they looked at patients who had two or more instances of high systolic blood pressure (above 140 mmHg) within the first 48 hours of admission. The “aggressive management”  group received one or more oral or intravenous doses of antihypertensive medication that they weren’t taking before admission to hospital. Unfortunately, a troubling trend emerged. 

Nora [00:08:48]:

Not only was aggressive blood pressure management linked to a higher risk of needing a transfer to the intensive care unit, but it was also associated with a higher risk of acute kidney injury, elevated B-type natriuretic peptide, increased troponin, and a hypotensive episode with systolic blood pressure dipping below 100 mmHg. Notably, those risks were highest in patients who received intravenous antihypertensive treatment. What was the key takeaway? There are potential dangers associated with the aggressive treatment of elevated blood pressure in older adults hospitalized for non-cardiac conditions. One expert emphasized that this research adds to the mounting evidence that such intensive hypertension treatment can be harmful when there are no signs of end-organ damage. So where do we go from here? The expert recommended a more measured approach for patients with asymptomatic elevated blood pressures. They said we should focus on addressing the underlying causes of temporary blood pressure increases—such as anxiety, pain, nausea, and urinary retention—rather than resorting to blood pressure-lowering medications (especially intravenous ones!). This study underscores the importance of nuanced, patient-centered care, especially in managing conditions as multifaceted as hypertension in older adults. It also challenges us to critically evaluate our practices and adapt our approaches to ensure the safest and most effective care for our patients.

Peter [00:10:02]:

Thank you for that Nora! To everyone listening, before we wrap up, remember to hit that subscribe button so you don't miss any of our episodes. And because we want to make this podcast as helpful as possible, if you have any feedback for us, please write to us at support@medmastery.com and share your thoughts. Last, but not least, a quick word about Medmastery. We’ve been honored with multiple awards for our digital education resources, and are highly commended by the British Medical Association. Our internationally accredited Continuing Medical Education courses are trusted by residency programs and universities worldwide. Hundreds of users on Trustpilot rate us as excellent, and 21% of our paying members said Medmastery’s courses empowered them to save lives. Our faculty teaches and trains at prestigious universities around the world.

Peter [00:11:02]:

With one membership, you unlock access to all courses, workshops, webinars, and more, allowing you to refresh your knowledge, learn new skills, and achieve your career goals. Sign up for a free trial at Medmastery.com today and start learning from the best in the field! Back to you Nora!

Nora [00:11:12]:

Thanks so much for listening everyone! We hope you’ve enjoyed this episode and found it helpful! Can we ask you for a quick favor? Reviews help us grow our podcast so we can help more people, so, could you leave us a quick review before you go? It’ll only take a minute! Anyhow, we wish you a great week! And we'll see you again next time! Bye for now!