More information about text formats
May Systemic Atherosclerotic Risk Classification Bring a Different
Glance to the CORONARY Study?
Running Title; the CORONARY Study and Atherosclerosis Classification
Sinan DEMIRTAS, Medical School of Dicle University, Department of
Cardiovascular Surgery email@example.com
Oguz KARAHAN, Medical School of Dicle University, Department of
Cardiovascular Surgery firstname.lastname@example.org
Corresponding Author Address: Oguz KARAHAN, MD
Medical School of Dicle University
Department of?Cardiovascular Surgery
The renal sub-study of the CORONARY Study was presented recently. Despite the fact that the results were exciting, some noteworthy determinants which may affect the given preliminary outcomes seems to be neglected in the study. For example, the distribution of coronary atherosclerosis and previous percutaneous coronary interventions were not presented. We want to indicate these determinants shortly.
Editor, Garg et al. have recently published a kidney sub-study analytic protocol of CORONARY Study in BMJ Open, entitled "Coronary Artery Bypass Grafting Surgery Off- or On-pump Revascularization Study (CORONARY): kidney sub-study analytic protocol of an international randomized controlled trial" (1). CORONARY is the largest multi-clinical trial comparing coronary artery bypass graft (CABG) surgery done with and without a bypass pump in widely ethnicity. Despite the results are not reported, this trial is focuses on multifactorial systemic interactions.
We read the article of Garg et al. with great interest. The article in question performed an excellent sub-study of a large ongoing study, comprehensively contemplating the subject in an enlightening and objective manner. We were convinced about their report and we look forward to publication of the comprehensive results. However, we want to draw attention to some topics which may have various effects on the outcomes while the study is still continuing.
Moderate or severe renal failure is already known as a worsening factor that reduces 5-year survival rates after CABG surgery (2). Additionally, the heart-lung pump leads to changes in blood properties and body accustomed pulsatile flow. Either pump structure or essential variables such as prime solutions stimulate a generalized inflammatory response and increased exposure to oxidative stress (3).External circulation is a substantial potential risk for renal tissues as mentioned as similar in Garg et al sub-study report (1). Also, there were numerous excellent clinical studies reported in the literature such as presented by Abu-Omar et al that reported creatinine clearance is significantly lower in postoperative period of on-pump CABG patients (4). These described determinants are important predictive markers for comparing on-pump and off-pump coronary artery bypass grafting. However, we suggest that the classification of coronary artery severity and previous or lateen percutaneous coronary interventions should be presented if renal functions are investigated in the coronary interventions. The performed diagnostic and therapeutic cardiac catheterizations necessitate intravascular administration of iodinated contrast medium that leads to noteworthy nephrotoxic disorders (5). The elapsed time after cardiac catheterization to operation is also important. Creatinine levels are usually achieves peak values in 3 to 5 days and return to base levels in 1 to 3 weeks after the catheterization (5). Types of procedures and repetitions of transactions are important determinants for contrast exposure. Additionally, heart failure, anterior myocardial infarction, cardiogenic shock and severity of coronary artery disease increase the risk of the nephrotoxic outcomes after catheterizations (6,7). Nevertheless, renal function was found to be related to severity of coronary artery disease in people aged over 70 according to the Rotterdam Study Data presented by Barzouhi et al (8). To sum up, we track the CORONARY study results. So, reading of this preliminary report is very exciting. However, we suggest that presenting other demographic data and factors that impact the outcomes such as "classification of coronary artery atherosclerosis severity" will be beneficial for the clarification of the obtained results. We therefore believe that severity of coronary artery atherosclerosis may affect the outcomes of on- pump or off-pump CABG.
1. Garg AX, Devereaux PJ, Yusuf S, et al. Coronary Artery Bypass Grafting Surgery Off- or On-pump Revascularisation Study (CORONARY): kidney substudy analytic protocol of an international randomized controlled trial. BMJ Open 2012;2:e001080.
2. Brown JR, Cochran RP, MacKenzie TA, Furnary AP, Kunzelman KS, Ross CS, Langner CW, Charlesworth DC, Leavitt BJ, Dacey LJ, Helm RE, Braxton JH, Clough RA, Dunton RF, O'Connor GT; Northern New England Cardiovascular Disease Study Group.Long-term survival after cardiac surgery is predicted by estimated glomerular filtration rate. Ann Thorac Surg. 2008 Jul;86(1):4 -11.
3. P. Biglioli, A. Cannata, F. Alamanni, M. Naliato, M. Porqueddu, M. Zanobini, E. Tremoli, A. Parolari. Biological effects of off-pump vs. on- pump coronary artery surgery: focus on inflammation, hemostasis and oxidative stress. Eur J Cardiothorac Surg, 24 (2) (2003), pp. 260-269
4. Abu-Omar Y, Taghavi FJ, Navaratnarajah M, Ali A, Shahir A, Yu LM, Choong CK, Taggart DP. The impact of off-pump coronary artery bypass surgery on postoperative renal function. Perfusion. 2012 Mar;27(2):127-31. Epub 2011 Nov 24.
5. Schweiger MJ, Chambers CE, Davidson CJ, Blankenship J, Bhalla NP, Block PC, Dervan JP, Gasperetti C, Gerber L, Kleiman NS, Krone RJ, Phillips WJ, Siegel RM, Uretsky BF, Laskey WK. Prevention of contrast induced nephropathy: recommendations for the high risk patient undergoing cardiovascular procedures. Catheter Cardiovasc Interv. 2007 Jan;69(1):135- 40.
6. Pradhan J, Niraj A, Afonso L Determinants of amount of contrast utilized in patients undergoing percutaneous coronary procedures. Coron Artery Dis. 2007 Jun;18(4):275-82.
7. Shoukat S, Gowani SA, Jafferani A, Dhakam SH. Contrast-induced nephropathy in patients undergoing percutaneous coronary intervention. Cardiol Res Pract 2010; 2010: 1-12.
8. El Barzouhi A, Elias-Smale S, Dehghan A, Vliegenthart-Proen?a R, Oudkerk M, Hofman A, Witteman JC. Renal function is related to severity of coronary artery calcification in elderly persons: the Rotterdam study. PLoS One. 2011 Feb 2;6(2):e16738.