RAS Blockers and AKI in Renal Patients Having Cardiac Cath
RAS Blockers and AKI in Renal Patients Having Cardiac Cath
Of the 208 patients in the study, 102 were randomly assigned to the continue ACEI/ARB group and 106 to the hold ACEI/ARB group. Complete follow-up was achieved in all patients. Baseline characteristics were well balanced between the 2 groups (Table I). Rates of diabetes were similar in both groups, although there was a trend toward higher rates of insulin used to treat diabetic patients in the continue ACEI/ARB group (24.5% vs 14.2%, P = .08). Both groups had a similar proportion of patients with a documented serum creatinine ≥ 1.7 mg/dL (150 μmol/L) within 3 months before cardiac catheterization (49.5% vs 45.8%, P = .94). All patients were on an ACEI/ARB (ACEI [72.1%] or ARB [27.9%]) prior to randomization. Precatheterization characteristics showed that patients were well hydrated with 3 mL kg h intravenous normal saline given at least 1 hour before the procedure, which was similar in both groups (396 mL vs 417 mL) (Table II). Baseline levels of serum creatinine were similar in the 2 groups (Table II). During cardiac catheterization, similar volumes of radioactive contrast were used and invasive hemodynamics were comparable between both groups (Table III).
The primary outcome of contrast-induced AKI occurred in 18.4% of patients randomized to continue ACE/ARBs, compared with 10.9% of patients in the hold ACEI/ARB group (HR in the hold ACE/ARB group 0.59, 95% CI 0.30–1.19, P = .16) (Table IV).
The secondary outcome of change in mean serum creatinine was 0.3 ± 0.5 mg/dL (24.1 ± 46.2 μmol/L) in the continue ACEI/ARB group, as compared with 0.1 ± 0.3 mg/dL (13.1 ± 22.6 μmol/L) in the hold ACEI/ARB group (P = .03) (Table IV).
At 72 hours post–follow-up, a clinical outcome of death, myocardial infarction, ischemic stroke, congestive heart failure, rehospitalization for cardiovascular cause, or need for dialysis occurred in 3.9% of the continue ACEI/ARB group, as compared with no events (0%) in the hold ACEI/ARB group (P = .0561) (Table IV). There was 1 death (out-of-hospital; 1.0% vs 0%), 1 ischemic stroke (1.0% vs 0%), and 3 rehospitalizations for a cardiovascular cause (2.9% vs 0%) in the continue ACEI/ARB group.
Congestive heart failure or hypertension (systolic blood pressure [SBP] > 160 mm Hg or diastolic blood pressure > 95 mm Hg) after cardiac catheterization occurred in 19.6% of patients in the continue ACEI/ARB group, as compared with 10.4% in the hold ACEI/ARB group (HR 0.53, 95% CI 0.27–1.05, P = .06) (Table IV).
There was no significant heterogeneity in the primary outcome in subgroups stratified according by age, diabetes or risk of contrast-induced AKI (Figure 1). In prespecified analyses, the primary outcome was stratified by tertiles using the Mehran Risk Score, a validated risk score for prediction of contrast-induced AKI. There was no significant heterogeneity in the primary outcome when stratified for the Mehran risk score. However, in patients with a moderate-high Mehran risk score (6–10), the secondary end point measuring the absolute rise in serum creatinine postcardiac catheterization was 0.3 ± 0.4 mg/dL (27.5 ± 32.9 μmol/L) in the continue ACEI/ARB group, as compared with 0.1 ± 0.2 mg/dL (4.7 ± 16.7 μmol/L) in the hold ACEI/ARB group (P = .01). A similar trend was also seen in patients with a high Mehran risk score (>10; 0.4 ± 0.7 mg/dL [31.3 ± 59.1 μmol/L] vs 0.2 ± 0.2 mg/dL [17.2 ± 20.0 μmol/L], P = .14; P interaction = .02).
(Enlarge Image)
Figure 1.
Risk ratios for the primary end point in prespecified subgroups.
In exploratory analyses, we estimated the creatinine clearance for all patients using the Cockcroft-Gault formula. Also, we estimated the GFR for all patients using the Modification of Diet in Renal Disease formula. Regardless of the method used to assess renal function, there was a strong trend toward reduced AKI after cardiac catheterization in favor of holding ACEI/ARB (change in creatinine clearance: −6.2 ± 10.0 mL/min vs −3.8 ± 7.7 mL/min, P = .06; change in GFR: −5.8 ± 9.5 mL/min vs −3.6 ± 7.2 mL/min, P = .06) (Figure 2).
(Enlarge Image)
Figure 2.
Estimated change in renal function after cardiac catheterization using either the Cockcroft-Gault formula (estimated creatinine clearance [CrCl]) or the Modification of Diet in Renal Disease formula (estimated GFR).
Results
Of the 208 patients in the study, 102 were randomly assigned to the continue ACEI/ARB group and 106 to the hold ACEI/ARB group. Complete follow-up was achieved in all patients. Baseline characteristics were well balanced between the 2 groups (Table I). Rates of diabetes were similar in both groups, although there was a trend toward higher rates of insulin used to treat diabetic patients in the continue ACEI/ARB group (24.5% vs 14.2%, P = .08). Both groups had a similar proportion of patients with a documented serum creatinine ≥ 1.7 mg/dL (150 μmol/L) within 3 months before cardiac catheterization (49.5% vs 45.8%, P = .94). All patients were on an ACEI/ARB (ACEI [72.1%] or ARB [27.9%]) prior to randomization. Precatheterization characteristics showed that patients were well hydrated with 3 mL kg h intravenous normal saline given at least 1 hour before the procedure, which was similar in both groups (396 mL vs 417 mL) (Table II). Baseline levels of serum creatinine were similar in the 2 groups (Table II). During cardiac catheterization, similar volumes of radioactive contrast were used and invasive hemodynamics were comparable between both groups (Table III).
Primary and Secondary Outcomes
The primary outcome of contrast-induced AKI occurred in 18.4% of patients randomized to continue ACE/ARBs, compared with 10.9% of patients in the hold ACEI/ARB group (HR in the hold ACE/ARB group 0.59, 95% CI 0.30–1.19, P = .16) (Table IV).
The secondary outcome of change in mean serum creatinine was 0.3 ± 0.5 mg/dL (24.1 ± 46.2 μmol/L) in the continue ACEI/ARB group, as compared with 0.1 ± 0.3 mg/dL (13.1 ± 22.6 μmol/L) in the hold ACEI/ARB group (P = .03) (Table IV).
Clinical Outcomes
At 72 hours post–follow-up, a clinical outcome of death, myocardial infarction, ischemic stroke, congestive heart failure, rehospitalization for cardiovascular cause, or need for dialysis occurred in 3.9% of the continue ACEI/ARB group, as compared with no events (0%) in the hold ACEI/ARB group (P = .0561) (Table IV). There was 1 death (out-of-hospital; 1.0% vs 0%), 1 ischemic stroke (1.0% vs 0%), and 3 rehospitalizations for a cardiovascular cause (2.9% vs 0%) in the continue ACEI/ARB group.
Safety Outcome
Congestive heart failure or hypertension (systolic blood pressure [SBP] > 160 mm Hg or diastolic blood pressure > 95 mm Hg) after cardiac catheterization occurred in 19.6% of patients in the continue ACEI/ARB group, as compared with 10.4% in the hold ACEI/ARB group (HR 0.53, 95% CI 0.27–1.05, P = .06) (Table IV).
Prespecified Subgroups
There was no significant heterogeneity in the primary outcome in subgroups stratified according by age, diabetes or risk of contrast-induced AKI (Figure 1). In prespecified analyses, the primary outcome was stratified by tertiles using the Mehran Risk Score, a validated risk score for prediction of contrast-induced AKI. There was no significant heterogeneity in the primary outcome when stratified for the Mehran risk score. However, in patients with a moderate-high Mehran risk score (6–10), the secondary end point measuring the absolute rise in serum creatinine postcardiac catheterization was 0.3 ± 0.4 mg/dL (27.5 ± 32.9 μmol/L) in the continue ACEI/ARB group, as compared with 0.1 ± 0.2 mg/dL (4.7 ± 16.7 μmol/L) in the hold ACEI/ARB group (P = .01). A similar trend was also seen in patients with a high Mehran risk score (>10; 0.4 ± 0.7 mg/dL [31.3 ± 59.1 μmol/L] vs 0.2 ± 0.2 mg/dL [17.2 ± 20.0 μmol/L], P = .14; P interaction = .02).
(Enlarge Image)
Figure 1.
Risk ratios for the primary end point in prespecified subgroups.
In exploratory analyses, we estimated the creatinine clearance for all patients using the Cockcroft-Gault formula. Also, we estimated the GFR for all patients using the Modification of Diet in Renal Disease formula. Regardless of the method used to assess renal function, there was a strong trend toward reduced AKI after cardiac catheterization in favor of holding ACEI/ARB (change in creatinine clearance: −6.2 ± 10.0 mL/min vs −3.8 ± 7.7 mL/min, P = .06; change in GFR: −5.8 ± 9.5 mL/min vs −3.6 ± 7.2 mL/min, P = .06) (Figure 2).
(Enlarge Image)
Figure 2.
Estimated change in renal function after cardiac catheterization using either the Cockcroft-Gault formula (estimated creatinine clearance [CrCl]) or the Modification of Diet in Renal Disease formula (estimated GFR).
