2005 Vol. 2, No. 3
The metabolic, neurohumoral, and hemodynamic milieu of renal insufficiency appears to accelerate the atherosclerotic process, cause vascular calcification, heighten the rates of plaque rupture, and very importantly worsens myocardial systolic and diastolic function. Because of long-standing hypertension, activation of the renin-angiotensin aldosterone system, and anemia, left ventricular hypertrophy (LVH) is common in chronic kidney disease (CKD) and end-stage renal disease (ESRD). As a result of ischemic heart disease, LVH, and electrolyte shifts, there are higher rates of arrhythmias (atrial, ventricular, heart block) and sudden cardiac death with ESRD. These arrhythmias occur at higher rates during hemodialysis. Lastly, although mainly coincident to the above processes, there is commonly aortic valve sclerosis and mitral annular calcification in ESRD which predispose patients to endocarditis.
The modern day, worldwide epidemics of obesity and hypertension (HTN) are central drivers of a secondary epidemic of type 2 diabetes with combined chronic kidney disease (CKD) and cardiovascular disease (CVD).' Approximately half of those with diabetes will develop CKD.2 Conversely, half of all cases of end-stage renal disease (ESRD) are due to diabetic nephropathy. With the aging of the general population and cardiovascular care shifting towards the elderly, an understanding of why decreasing levels of renal function act as a major adverse prognostic factor after a variety of cardiac events is imperative. The heart and kidney are inextricably linked via hemodynamic and neurohumoral function (Fig. 1). Considerable evidence shows that CKD accelerates atherosclerosis, myocardial disease, valvular disease, and promotes an array of cardiac arrhythmias.1
Objective To assess the effects of early correction of anemia with recombinant human erythropoietin (rHuEPO) on the develop-ment and progression of left ventricular hypertrophy (LVH) in patients with mild-to-moderate chronic renal insufficiency (CRI) who are not on hemodialysis. Methods A total of 158 patients with serum creatinine from 147jJ.mol/L to 40()p_mol/L were enrolled in this prospective, multicenter study. Eighty-six patients with hemoglobin (Hb) 1 lOg/L (Group A). Forty patients with comparable Hb concentration ( l lOg/L and without rHuEPO treatment (Group C) were served as controls. Left ventricular mass index (LVMI) was evaluated by echocardiography at baseline and every 3 months for 2 years. Results There was no difference in age, gender, etiology of renal failure, blood pressure and cardiovascular risk factors among the 3 groups. At baseline, the prevalence of LVH was 72.1% in group A, 72.5% in group B and 59.4% in group C. LVMI was inversely correlated with Hb levels (r=0.70, P<0.01). During the 2-year period, the mean LVMI decreased from 142.6±25.7g/m: to 132.4±18.5 g/nr in group A, while increased significantly in both group B and group C. The mean Hb concentration increased from 93.8±i4.6g/L to 111.2±10.3g/L (P<0.05) in group A, but tended to decrease in group B and group C. There was no significant change of the mean blood pressure, number of anti-hypertensive drugs and serum creatinine concentrations in all 3 groups. However, patients' serum creatinine doubled more often in group B and group C than in group A. Conclusions LVH was common in predialysis CRI patients and was associated with the severity of anemia. Early intervention with rHuEPO may reverse LVH in these patients.
Objective To evaluate the effect of revascularization of the renal artery on urinary microglobulin in patients with coronary artery disease and significant renal artery stenosis (RAS). Methods Forty-four patients with coronary artery disease and severe RAS (luminal narrowing >70%) underwent percutaneous transluminal renal artery angioplasty (PTRA) and stenting, as well as percutane-ous coronary intervention. The urine -microglobulin ( o^-MG) and P2-Cmicroglobulin (P,-MG) at baseline and at 3 months after the procedures were measured. Procedural success rate, procedural complications, serum creatinine concentration at baseline and at 3-months were also recorded. Results At 3-months after the renal revascularization therapy, there was no significant change of urine o^-MG compared with that of the baseline, however, the urine (3,-MG decreased significantly 3-months after the treatment (237+ 187^g/L vs 377±173 |J.g/L, P<0.01). Multivariate analysis revealed that persistent elevation of urine was an independent predictor of severe events (including re-admission and renal failure) after renal revascularization therapy in patients with severe RAS (OR=3.01, 95% Cl 1.01-8.95, P=0.036). Conclusions In patients with coronary artery disease and severe RAS, revascularization with PTRA and stenting may improve renal tubular function, but a continuous high level of urinary microglobulins after intervention is associated with more frequent re-hospitalization and renal failure.
As people age, cardiovascular structure and function change and this is superimposed on by specific pathophysiologic disease mechanism. In addition to lipid levels, diabetes, sedentary lifestyle, and genetic factors that are known risks for coronary disease, hypertension, and stroke - the quintessential cardiovascular (CV) diseases related to atherosclerosis within our society - advancing age unequivocally confers the major risk. (Fig. 1) Mortality due to cardiovascular disease is more than any other disease and creates enormous costs for the health care system. The main underlying problem in cardiovascular disease is atherosclerosis, a process that obstructs major arteries with lipid deposits and cell accumulation. Decreased kidney function (estimated GFR < 70 mL/min/1.73 m2) is an independent risk factor for cardiovascular disease and all-cause mortality in the general population.
Cardiovascular disease is an important cause of mortality in the chronic kidney disease (CKD) population. This review discusses cardiac surgery in the CKD population and considers postoperative acute renal failure (ARF). CKD patients have worse outcomes following coronary artery bypass grafting (CABG) and cardiac valvular surgery than the general population. However, surgical revascularization is an effective treatment for coronary artery disease (CAD) in this population and may be associated with improved survival over percutaneous intervention (PCI) in advanced CKD. Cardiac surgery in the CKD population requires careful perioperative planning and management. Acute renal failure (ARF) is a serious complication following cardiac surgery, occurring in 1 to 8% of cases. Management of postoperative ARF is largely supportive and emphasis is placed on preoperative risk stratification and prevention.
Many patients with congestive heart failure (CHF) fail to respond to maximal CHF therapy and progress to end stage CHF with many hospitalizations, very poor quality of life, end stage renal failure, or die of cardiovascular complications within a short time. One factor that has generally been ignored in many of these patients is the fact that they are often anemic. The anemia is due mainly to renal failure but also to the inhibitory effects of cytokines on the bone marrow. Anemia itself may further worsen the cardiac function and make the patients resistant to standard CHF therapies. Indeed anemia has been associated with increased severity of CHF, increased hospitalization, worse cardiac function and functional class, higher doses of diuretics, worsening of renal function and reduced quality of life. In both controlled and uncontrolled studies the correction of the anemia with erythropoietin (EPO) and oral or IV iron is associated with improvement in all these parameters. EPO itself may also play a direct role in improving the heart unrelated to the improvement of the anemia. Anemia may also play a role in the worsening of coronary heart disease even without CHF.
Mitral annular calcification (MAC) and aortic valve calcification (AVC) are the most common valvular and perivalvular abnormalities in patients with chronic kidney disease (CKD). Both MAC and AVC occur at a younger age in CKD patients than in the general population. AVC progresses to aortic stenosis and mild aortic stenosis progresses to severe aortic stenosis at a more rapid rate in patients with CKD than in the general population. The use of calcium-free phosphate binders in such patients may reduce the calcium burden in valvular and perivalvular structures and retard the rate of progression of aortic stenosis. Despite high rates of morbidity and mortality, the prognosis associated with valve surgery in patients with CKD is better than without valve surgery. Infective endocarditis remains an important complication of CKD, particularly in those treated with hemodialysis.
Crdiovascular diseases (CVD) incur a heavy burden of morbidity and mortality among patients with chronic kidney disease (CKD), particularly among the elderly. It is estimated that about 22-25% of all adults beyond the age of 65 years have moderate or severe renal dysfunction.
Chronic kidney disease (CKD) is a significant contributor to cardiovascular morbidity and mortality. Patients with CKD are known to have a greater prevalence of cardiovascular disease than the general population,1 and patients with concurrent CKD and coronary artery disease (CAD) have greater mortality than patients without CKD.2 4 The rate of cardiovascular mortality is approximately 50%, five to 10 times higher than the general population.
Objectives: To report the clinical experience of combined interventional procedures in the treatment of elderly patients with coexisting two or more cardiovascular diseases in our medical center, and to assess the feasibility, safety and therapeutic efficacy of this management strategy. Methods: Patients were selected to the study if: 1) age >65 years; 2) with coexistence of two or more cardiovascular diseases which are indications for interventional therapy: 3) patients' general condition and organ functions allow the performance of combined multiple procedures; 4) the predicted procedure time is within 150 min; 5) the predicted contrast medium dosage is within 300 ml. The criteria we analyzed included procedural type, procedural time, fluoroscopy time, dosage of contrast medium, success rates of the procedures, complications and in-hospital mortality. All patients were followed up for 30.4 ± 9.3 months, to determine the all-cause mortality, recurrence rates and adverse cardiac events. Results: From January 2000 to December 2004, combined interventional procedures were performed on 136 patients, with 2 procedures on 134 patients and 3 procedures on 2 patients. The mean procedure time was 115.4 ± 11.6 min, the mean fluoroscopy time was 35.7 ± 9.3 min, and the mean dosage of contrast medium used was 183.6 ± 19.4 ml. Procedural success rate was 1009K no procedure related death or major complications occurred. Conclusion: Performed by a competent team, combined interventional procedures in elderly patients with multiple cardiovascular diseases were feasible and relatively safe.
In the early years of coronary interventions, when a single lesion was found, the question then was asked whether it was feasible and safe to dilate right away the lesion with plain old balloon angioplasty (ad hoc FOB A) or to call in a senior interventional cardiologist to do FOB A on a later date. If lesions were found in more than one coronary artery territories, then the interventional cardiologists had to pull his or her hair and asked whether it was feasible and safe to dilate right away the other lesion(s) at the same session. More than 20 years later, at this present time, with nearly perfect outcomes due to stent availability and high level of experiences from operators, the question of multiple coronary stenting in one session is neither problematic nor relevant. However, if not all lesions are taken care immediately or in near future sessions, the question would be whether the patient receives standard of care as there is no complete revascularization.