“Should I consider cardiac CT angiography in my 76-year-old male patient with chest pain of unclear origin?”  

Probably not!1-4 Although the 2021 AHA/ACC Chest Pain Guidelines have generally widened the scope of indications for cardiac CT angiography (CCTA) to patients at low to intermediate risk of coronary artery disease (CAD) presenting with acute coronary syndrome (ACS)1 (with or without known CAD), several caveats should be considered before ordering this test. In general preference is given to patients with the following characteristics: 

  • Age sixty-five years of age or younger.  Elderly are not ideal candidates for CCTA as the calcium burden may be too high, rendering the test non-diagnostic due to the interference with proper coronary artery lumen assessment. Women tend not to accumulate as much calcium and their age threshold may be increased to 70 years. Some studies like the ROMICAT II Trial extended the age up to 74 years.4 
  • BMI <40.2
  • Sinus rhythm. Atrial fibrillation can be circumvented with expanded padding techniques, albeit at higher radiation exposure.2
  • Without coronary stents, unless their stents are > 3.0 mm in diameter (eg, in left main, very proximal left anterior descending, circumflex or right coronary stents).2
  • Without high coronary calcium burden, or without multiple risk factors for CAD (eg, type 2 diabetes, hypertension, hyperlipidemia) in the setting of typical anginal chest pain.1
  • Other technical requirements: must be able to hold breath during procedure, not have contraindications to beta blockers (ideal heart rate <60 bpm), not have an iodinated contrast allergy, and have stable kidney function.2

Despite these caveats, many patients may still be able to undergo CCTA to help exclude coronary causes of their chest pain.  For example, a 49-year-old patient at low to intermediate risk of CAD presenting with atypical chest pain can potentially undergo CCTA and, if negative, be discharged the same day!4  

In our patient, however, given his older age, CCTA is likely to be non-diagnostic and proceeding to an alternative test, such as stress test or invasive coronary angiography (depending on circumstances and pre-test probability), may be a better option.  

Bonus Pearl: Did you know that, as a “bonus”,  CCTA provides a “free” look at the lungs, calcium score (used largely in asymptomatic patients to help weigh pros and cons of starting a statin)3, and other cardiopulmonary structures that may hint at alternative diagnoses for the cause of chest discomfort and/or dyspnea?

Contributed by Eldin Duderija MD, Cardiologist, Mercy Clinic, St. Louis, Missouri

 

Liked this post? Download the app on your smart phone and sign up below to catch future pearls right into your inbox, all for free!

Subscribe to Blog via Email

Enter your email address to subscribe to this blog and receive notifications of new posts by email.

References:

  1. Gulati M, Levy P, et al. 2021 AHA/ACC/ASE/CHEST/SAEM/SCCT/SCMR Guideline for the Evaluation and Diagnosis of Chest Pain. J Am Coll Cardiol. 2021;78:e187–e285. https://pubmed.ncbi.nlm.nih.gov/34709879/
  2. Raff GL, Chinnaiyan KM, Cury RC, Garcia MT, Hecht HS, Hollander JE, O’Neil B, Taylor AJ, Hoffmann U; Society of Cardiovascular Computed Tomography Guidelines Committee. SCCT guidelines on the use of coronary computed tomographic angiography for patients presenting with acute chest pain to the emergency department: a report of the Society of Cardiovascular Computed Tomography Guidelines Committee. J Cardiovasc Comput Tomogr 2014;8:254-71. doi: 10.1016/j.jcct.2014.06.002. Epub 2014 Jun 12. PMID: 25151918. https://pubmed.ncbi.nlm.nih.gov/25151918/
  3. Hecht H, Blaha MJ, Berman DS, Nasir K, Budoff M, Leipsic J, Blankstein R, Narula J, Rumberger J, Shaw LJ. Clinical indications for coronary artery calcium scoring in asymptomatic patients: Expert consensus statement from the Society of Cardiovascular Computed Tomography. J Cardiovasc Comput Tomogr 2017;11:157-168. doi: 10.1016/j.jcct.2017.02.010. Epub 2017 Feb 24. PMID: 28283309. https://pubmed.ncbi.nlm.nih.gov/28283309/
  4. Hoffmann, Udo, et al. “Coronary CT angiography versus standard evaluation in acute chest pain.” N Engl J Med 2012;367:299-308. https://www.nejm.org/doi/full/10.1056/nejmoa1201161

Disclosures: The listed questions and answers are solely the responsibility of the author and do not necessarily represent the official views of Mercy Hospital-St. Louis, Massachusetts General Hospital, Harvard Catalyst, Harvard University, their affiliate academic healthcare centers, or its contributors. Although every effort has been made to provide accurate information, the author is far from being perfect. The reader is urged to verify the content of the material with other sources as deemed appropriate and exercise clinical judgment in the interpretation and application of the information provided herein. No responsibility for an adverse outcome or guarantees for a favorable clinical result is assumed by the author. Thank you!

 

“Should I consider cardiac CT angiography in my 76-year-old male patient with chest pain of unclear origin?”  

What’s the evidence that REGEN-COV (casirivimab and imdevimab) monoclonal antibody cocktail is effective in the post-exposure prophylaxis of Covid-19?

The U.S. FDA has issued an Emergency Use Authorization (EUA) for the emergency use of REGEN-COV in adult and pediatric populations (≥12 years of age and older weighing> 40 kg) who are at high risk* of progression to severe COVID-19— including hospitalization or death— and who are not fully vaccinated or are not expected to mount an adequate immune response to the vaccine (eg, immunocompromised state).1  This recommendation is based on a randomized controlled trial involving individuals enrolled within 96 hours of exposure to a known Covid-19 case (Covid-10 Phase 3 Prevention Trial).2

In this trial, the primary efficacy end point was the development of symptomatic SARS-CoV-2 infection through day 28  in participants who did not have SARS-CoV-2 infection  by PCR or serology at the time of enrollment. Symptomatic SARS-CoV-2 infection developed in 1.5% of treatment group (vs 7.8% in placebo group) with 81.4% relative risk reduction (P<0.001); 66% reduction was observed when symptomatic and asymptomatic infections were combined.  Duration of symptoms and the magnitude and duration of detectable RNA were also lower in the REGEN-COV group compared to placebo. Therapy was well tolerated.2

In the same study, in a subgroup analysis of those who were seropositive at the time of enrollment REGEN-COV lowered the risk of symptomatic disease (0.4% vs 2.3% in the placebo group) with relative risk reduction of 81%, though not statistically significant (P=0.14).  This may be why the FDA EUA extended to certain vaccinated groups as well since to date there are no published trials on the use of REGEN-COV as post-exposure prophylaxis in vaccinated individuals.

*High risk group included ≥65 years of age, BMI≥25 kg/m2, diabetes, immunocompromised state, cardiovascular disease or hypertension, chronic lung disease, sickle cell disease and neurodevelopment disorders.

Liked this post? Download the app on your smart phone and sign up below to catch future pearls right into your inbox, all for free!

Subscribe to Blog via Email

Enter your email address to subscribe to this blog and receive notifications of new posts by email.

References

  1. Fact sheet for health care providers emergency use authorization (EUA) of REGEN-COV. https://www.fda.gov/media/145611/download. Accessed September 15, 2021.
  2. O’Brien MP. Forleo-Neto E, Musser BJ et al. Subcutaneous REGEN-COV antibody combination to prevent Covid-19. N Engl J Med 2021, August 4, 2021. https://www.nejm.org/doi/full/10.1056/NEJMoa2109682

 

Disclosures: The listed questions and answers are solely the responsibility of the author and do not necessarily represent the official views of Mercy Hospital-St. Louis, Massachusetts General Hospital, Harvard Catalyst, Harvard University, their affiliate academic healthcare centers, or its contributors. Although every effort has been made to provide accurate information, the author is far from being perfect. The reader is urged to verify the content of the material with other sources as deemed appropriate and exercise clinical judgment in the interpretation and application of the information provided herein. No responsibility for an adverse outcome or guarantees for a favorable clinical result is assumed by the author. Thank you!

What’s the evidence that REGEN-COV (casirivimab and imdevimab) monoclonal antibody cocktail is effective in the post-exposure prophylaxis of Covid-19?

How does obesity lower serum brain natriuretic peptide (BNP) levels in patients with heart failure?

The association between high body mass index (BMI) and low serum BNP levels  has been reported in heart failure patients with diminished or preserved left ventricular systolic function (1).  

However, The exact mechanism underlying the inverse relationship of BNP levels with BMI is unclear.  Decreased production of BNP by myocytes, increased clearance of BNP and decreased sensitivity of the myocytes to stretch have been proposed (1). 

Of interest, in obese patients who undergo gastric bypass surgery, serum BNP levels increases significantly postoperatively and correlates with weight loss  (2).  

If you liked this post, sign up under MENU and catch future pearls right into your mailbox!

 

References 

  1. Stavrakis S, Pakala A, Thomas J et al. Obesity, brain natriuretic peptide levels and mortality in patients hospitalized with heart failure and preserved left ventricular systolic function. Am J Med Sci 2013;345:211-217. https://www.ncbi.nlm.nih.gov/pubmed/23422653
  2. Changchien EM, Shushmita A, Betti F, et al. B-type natriuretic peptide increases after gastric bypass surgery and correlates with weight loss. Surg Endosc 2011;25:2338-2343. https://www.ncbi.nlm.nih.gov/pubmed/21424205
How does obesity lower serum brain natriuretic peptide (BNP) levels in patients with heart failure?