186. Case Report: Coronary Artery Bypass Grafting: An Iatrogenic Left to Right Cardiac Shunt – SUNY Downstate

CardioNerds (Amit Goyal and Daniel Ambinder) and guest host, Dr. Priya Kothapalli (UT Austin fellow and CardioNerds Ambassador), join SUNY Downstate cardiology fellows, Dr. Eric Kupferstein and Dr. Gautham Upadhya to discuss a case about a patient who had coronary artery bypass grafting that was complicated by a LIMA grafted to the great cardiac vein. Dr. Alan Feit (Professor of Medicine, SUNY Downstate) provides the E-CPR for this episode. Dr. Moritz Wyler von Ballmoos (Director, robotic cardiac and vascular surgery for Houston Methodist Cardiovascular Surgery Associates) provides a special perspective regarding coronary artery bypass grafting as it relates to this case. Episode introduction with CardioNerds Clinical Trialist Dr. Jana Lovell (Johns Hopkins).

Left Internal Mammary Artery (LIMA) to Left Anterior Descending (LAD) artery anastomosis is the cornerstone of Coronary Artery Bypass Graft (CABG) surgery. Anastomosis of the LIMA to the Great Cardiac Vein (GCV) is a known but rare complication of the surgery. Currently there are no clear guidelines in regard to further management. We report a case of a LIMA to GCV anastomosis managed with a drug eluting stent (DES) to the mid LAD after ruling out a significant left to right heart shunt.

Jump to: Case mediaCase teachingReferences


Case Media – Coronary Artery Bypass Grafting: An Iatrogenic Left to Right Cardiac Shunt

Angiography

Episode Schematics & Teaching – Coronary Artery Bypass Grafting: An Iatrogenic Left to Right Cardiac Shunt

Pearls – Coronary Artery Bypass Grafting: An Iatrogenic Left to Right Cardiac Shunt

  1. Listen to the patient’s story. The patient determines when the angina is no longer stable angina.
  2. The placebo effect of our interventions should not be discounted.
  3. LIMA to GCV anastomosis creates a left to right cardiac shunt. A Qp:Qs greater than 1.5 signifies a significant shunt.
  4. Increasing the pressure in the coronary sinus may actually be beneficial to the patient.
  5. LIMA-LAD is remains the most efficacious and long lasting graft but why not other arterial grafts?

Notes – Coronary Artery Bypass Grafting: An Iatrogenic Left to Right Cardiac Shunt

Iatrogenic anastomosis of the LIMA to the GCV is a rare but noted complication of CABG surgery. Review of the literature has reported under 40 such cases of arteriovenous fistula formation in the coronary system. Detection of the anastomosis generally stems from recurrent angina which can be attributed to unresolved ischemia or coronary steal syndrome but also can be detected with new heart failure (namely right sided heart failure due to left to right shunting). Diagnosis is usually made with coronary angiography, but CT coronary angiography has also been reported. Due to the rarity of this complication, no clear guidelines are in place directing the management leaving it to the discretion of the various Heart Teams. Evaluating for signs of heart failure and/or ischemia, and measuring the Qp:Qs have been the most common signs directing management. Various options are available for closing the fistula and include coil or balloon embolization, vascular plugs, venous ligation or a covered stent. Redoing the surgery is also an option. Spontaneous closure of the fistula has also been reported. Lastly, if redo surgery is not performed then regardless of fistula closure, coronary intervention for the native diseased artery may be pursued to relieve symptoms.


References

  1. Boden et al; COURAGE Trial Research Group. Optimal medical therapy with or without PCI for stable coronary disease. N Engl J Med. 2007 Apr 12;356(15):1503-16. doi: 10.1056/NEJMoa070829. Epub 2007 Mar 26. PMID: 17387127.
  2. Maron et al; ISCHEMIA Research Group. Initial Invasive or Conservative Strategy for Stable Coronary Disease. N Engl J Med. 2020 Apr 9;382(15):1395-1407. doi: 10.1056/NEJMoa1915922. Epub 2020 Mar 30. PMID: 32227755; PMCID: PMC7263833.
  3. Klocke et al; ACC/AHA/ASNC guidelines for the clinical use of cardiac radionuclide imaging–executive summary: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (ACC/AHA/ASNC Committee to Revise the 1995 Guidelines for the Clinical Use of Cardiac Radionuclide Imaging). J Am Coll Cardiol. 2003 Oct 1;42(7):1318-33. doi: 10.1016/j.jacc.2003.08.011. PMID: 14522503.
  4. Chow et al; Diagnostic accuracy and impact of computed tomographic coronary angiography on utilization of invasive coronary angiography. Circ Cardiovasc Imaging. 2009 Jan;2(1):16-23. doi: 10.1161/CIRCIMAGING.108.792572. PMID: 19808560.
  5. Sheiban et al; Iatrogenic left internal mammary artery-coronary vein anastomosis treated with covered stent deployment via retrograde percutaneous coronary sinus approach. Catheter Cardiovasc Interv. 2006 Nov;68(5):704-7. doi: 10.1002/ccd.20842. PMID: 17039511.
  6. Lumley et al; Inadvertent left internal mammary artery (LIMA): great cardiac vein anastomosis. BMJ Case Rep. 2013 Feb 15;2013:bcr2012007450. doi: 10.1136/bcr-2012-007450. PMID: 23417930; PMCID: PMC3618535.
  7. Stout et al; AHA/ACC Guideline for the Management of Adults With Congenital Heart Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. J Am Coll Cardiol. 2019 Apr 2;73(12):e81-e192. doi: 10.1016/j.jacc.2018.08.1029. Epub 2018 Aug 16. Erratum in: J Am Coll Cardiol. 2019 May 14;73(18):2361-2362. PMID: 30121239.
  8. Olshansky B. Placebo and nocebo in cardiovascular health: implications for healthcare, research, and the doctor-patient relationship. J Am Coll Cardiol. 2007 Jan 30;49(4):415-21. doi: 10.1016/j.jacc.2006.09.036. Epub 2007 Jan 16. PMID: 17258086.
  9. Ido et al; Coronary sinus occlusion enhances coronary collateral flow and reduces subendocardial ischemia. Am J Physiol Heart Circ Physiol. 2001 Mar;280(3):H1361-7. doi: 10.1152/ajpheart.2001.280.3.H1361. PMID: 11179085.
  10. Banai et al; Coronary sinus reducer stent for the treatment of chronic refractory angina pectoris: a prospective, open-label, multicenter, safety feasibility first-in-man study. J Am Coll Cardiol. 2007 May 1;49(17):1783-9. doi: 10.1016/j.jacc.2007.01.061. PMID: 17466229.
  11. Gaudino et al; ATLANTIC (Arterial Grafting International Consortium) Alliance members. Arterial Grafts for Coronary Bypass: A Critical Review After the Publication of ART and RADIAL. Circulation. 2019 Oct 8;140(15):1273-1284. doi: 10.1161/CIRCULATIONAHA.119.041096. Epub 2019 Oct 7. PMID: 31934782.

CardioNerds Case Report Production Team

You are currently viewing 186. Case Report: Coronary Artery Bypass Grafting: An Iatrogenic Left to Right Cardiac Shunt – SUNY Downstate