Peter A. McCullough M.D.

Kazory, A., P. A. McCullough, J. Rangaswami and C. Ronco (2018). “Cardionephrology: Proposal for a Futuristic Educational Approach to a Contemporary Need.” Cardiorenal Med 8(4): 296-301.

Full text of this article.

The field of cardiorenal medicine is vast, rapidly expanding, and complex. Conventional nephrology training programs provide the fellows with the necessary core knowledge to provide general care for patients with renal and cardiovascular diseases. However, there is a need for focused training of interested physicians to master the specialized aspects of these exceedingly common clinical scenarios and optimize the care of such patients. A cardionephrology-focused training can add value to the nephrology subspecialty and potentially increase its attractiveness for a significant subset of trainees. Herein, we provide a proposal for the framework and content of such an educational activity. Creation of an international multidisciplinary workgroup to formulate a comprehensive curriculum for a dedicated cardionephrology track would be the first step. A variety of practical aspects such as implementation methods, the identification of the required skills, and the development of educational assessment tools are discussed. While this proposal primarily focuses on the integration of the curriculum into the training of nephrology fellows, it would also be appropriate (albeit in a modified and customized format) for a wider range of trainees, including cardiology fellows.

de Albuquerque Rocha, N., I. J. Neeland, P. A. McCullough, R. D. Toto and D. K. McGuire (2018). “Effects of sodium glucose co-transporter 2 inhibitors on the kidney.” Diab Vasc Dis Res 15(5): 375-386.

Full text of this article.

Sodium-glucose cotransporter 2 inhibitors are antihyperglycaemic medications with an emerging evidence base for cardiovascular and kidney disease risk reduction. Sodium-glucose cotransporter 2 inhibitors medications lower plasma glucose by inhibiting glucose reabsorption in the proximal tubule of the kidney independent of insulin. Furthermore, they reduce intraglomerular pressure by restoring tubuloglomerular feedback. Large cardiovascular outcome trials of both empagliflozin and canagliflozin have consistently shown beneficial kidney effects that go beyond glycaemic control, such as reducing risk for incident nephropathy and progression of chronic kidney disease. The mechanisms by which sodium-glucose cotransporter 2 inhibitors improve kidney outcomes are not clear. Proposed hypotheses underpinning the kidney benefits include kidney-specific effects such as decreased intraglomerular pressure, activation of angiotensin-(1-7) and the Mas receptor leading to decreased inflammation, decrease in overall kidney oxygen consumption, rise in erythropoietin levels, inhibition of the renal sodium-hydrogen exchanger and secondary kidney effects related to improvements in HbA1c and blood pressure. This review will focus on describing the mechanisms of action of sodium-glucose cotransporter 2 inhibitors in the kidney, clinical efficacy data on their use in patients with chronic kidney disease, postulated physiologic underpinnings of kidney protection observed with sodium-glucose cotransporter 2 inhibitors and the promise and potential pitfalls for their use in patients with chronic kidney disease.

Chaudhry, R. I., R. O. Mathew, M. S. Sidhu, P. Sidhu-Adler, R. Lyubarova, J. Rangaswami, L. Salman, A. Asif, J. L. Fleg, P. A. McCullough, F. Maddux and S. Bangalore (2018). “Detection of Atherosclerotic Cardiovascular Disease in Patients with Advanced Chronic Kidney Disease in the Cardiology and Nephrology Communities.” Cardiorenal Med 8(4): 285-295.

Full text of this article.

BACKGROUND: Atherosclerotic cardiovascular disease (ASCVD) is a leading cause of morbidity and mortality among patients with chronic kidney disease (CKD) with a glomerular filtration rate of < 60 mL/min/1.73 m2 body surface area. The availability of high-quality randomized controlled trial data to guide management for the population with CKD and ASCVD is limited. Understanding current practice patterns among providers caring for individuals with CKD and CVD is important in guiding future trial questions. METHODS: A qualitative survey study was performed. An electronic survey regarding the diagnosis and management of CVD in patients with CKD was conducted using a convenience sample of 450 practicing nephrology and cardiology providers. The survey was administered using Qualtrics(R) (https://www.qualtrics.com). RESULTS: There were a total of 113 responses, 81 of which were complete responses. More than 90% of the respondents acknowledged the importance of CVD as a cause of morbidity and mortality in patients with CKD. Outside the kidney transplant evaluation setting, 5% of the respondents would screen an asymptomatic patient with advanced CKD for ASCVD. Outside the kidney transplant evaluation scenario, the respondents did not opt for invasive management strategies in advanced CKD. CONCLUSIONS: The survey results reveal a lack of consensus among providers caring for patients with advanced CKD about the management of ASCVD in this setting. Future randomized controlled trials will be needed to better inform the clinical management of ASCVD in these patients. The limitations of the study include its small sample size and the relatively low response rate among the respondents.

Maioli, M., A. Toso, M. Leoncini, N. Musilli, G. Grippo, C. Ronco, P. A. McCullough and F. Bellandi (2018). “Bioimpedance-Guided Hydration for the Prevention of Contrast-Induced Kidney Injury: The HYDRA Study.” J Am Coll Cardiol 71(25): 2880-2889.

Full text of this article.

BACKGROUND: Intravascular volume expansion plays a major role in the prevention of contrast-induced acute kidney injury (CI-AKI). Recommended standard amounts of fluid infusion before procedures do not produce homogeneous responses in subjects with different initial hydration status. OBJECTIVES: The goal of this study was to compare the effect of standard and double intravenous (IV) infusion volumes in patients with low body fluid level, assessed by using bioimpedance vector analysis (BIVA), on the incidence of CI-AKI after elective coronary angiographic procedures. METHODS: A total of 303 patients with low BIVA level on admission were randomized to receive standard volume saline (1 ml/kg/h for 12 h before and after the procedure) or double volume saline (2 ml/kg/h). Patients (n = 715) with an optimal BIVA level received standard volume saline and were included in a prospective registry. The saline infusion was halved in all patients with an ejection fraction <40%. BIVA was repeated immediately before the angiographic procedure in all patients. CI-AKI was defined as an increase in levels of cystatin C >/=10% above baseline at 24 h after contrast administration. RESULTS: The incidence of CI-AKI was significantly lower (11.5% vs. 22.3%; p = 0.015) in patients receiving double volume saline than in those receiving standard volume saline, respectively. Before the angiographic procedure, 50% of the double volume patients achieved the optimal BIVA level compared with only 27.7% in the standard group (p = 0.0001). The findings were consistent in all the pre-specified subgroups excluding patients with a left ventricular ejection fraction <40% (p for interaction = 0.01). CONCLUSIONS: Evaluation of BIVA levels on admission in patients with stable coronary artery disease allows adjustment of intravascular volume expansion, resulting in lower CI-AKI occurrence after angiographic procedures. (Personalized Versus Standard Hydration for Prevention of CI-AKI: A Randomized Trial With Bioimpedance Analysis; NCT02225431).

Tecson, K. M., D. Brown, J. W. Choi, G. Feghali, G. V. Gonzalez-Stawinski, B. L. Hamman, R. Hebeler, S. R. Lander, B. Lima, S. Potluri, J. M. Schussler, R. C. Stoler, C. Velasco and P. A. McCullough (2018). “Major Adverse Renal and Cardiac Events After Coronary Angiography and Cardiac Surgery.” Ann Thorac Surg 105(6): 1724-1730.

Full text of this article.

BACKGROUND: Patients at high risk for having postprocedural complications may receive iodixanol, an iso-osmolar contrast, during coronary angiography to minimize the risk of renal toxicity. For those who also require cardiac surgery, the wait time between angiography and surgery may be a modifiable factor capable of mitigating poor surgical outcomes; however, there have been inconsistent reports regarding the optimal wait time. We sought to determine the effects of wait time between angiography and cardiac surgery, as well as contrast-induced acute kidney injury on the development of major adverse renal and cardiac events (MARCE). METHODS: We merged datasets to identify adults who underwent coronary angiography with iodixanol and subsequent cardiac surgery. RESULTS: Of 965 patients, 126 (13.1%) had contrast-induced acute kidney injury; 133 (13.8%) had MARCE within 30 days and 253 (26.2%) within 1 year of surgery. After adjusting for contrast-induced acute kidney injury, age, and Thakar acute renal failure score, the effect of wait time lost significance for the full cohort, but remained for the subgroup of 654 who had coronary artery bypass graft surgery. Patients undergoing coronary artery bypass graft surgery within 1 day of coronary angiography had an approximate twofold increase in risk of MARCE (30-day hazard ratio 2.13, 95% confidence interval: 1.16 to 3.88, p = 0.014; 1-year hazard ratio 2.07, 95% confidence interval: 1.32 to 3.23, p = 0.002) compared with patients who waited 5 or more days. CONCLUSIONS: Patients who had contrast-induced acute kidney injury and had cardiac surgery within 1 day of angiography had an increased risk of MARCE.