Dobutamine stress echocardiography in the diagnosis of asymptomatic ischemic heart disease in patients with chronic kidney disease--review of literature and single-center experience

Chronic kidney disease and orthostatic hypotension in hospitalised older adults

PURPOSE

Orthostatic hypotension (OH) may predispose older adults to health complications leading to functional impairment. Despite the central role of the kidney in blood pressure control, the contribution of renal function in orthostatic hypotension is poorly investigated. To verify the association between Chronic Kidney Disease (CKD) and OH a population of hospitalised elderly patients with comorbidities was studied.

MATERIALS AND METHODS

174 patients were consecutively admitted to Acute Geriatric Wards. On admission, patients underwent postural systolic (SBP) and diastolic (DBP) blood pressure evaluation by automatic oscillometric device after 10 min rest in lying position, and in standing position at time 0, 1, 3 and 5 min. CKD was assumed for estimated glomerular filtration rate (e-GFR) less than 60 mL/min/1.73 m2.

RESULTS

The mean age of the population enrolled was 74.4 ± 7.0. OH was found in 46.0% and CKD in 56.3% of patients, respectively. A lower e-GFR was observed in patients with (56.1 ± 16.7 mL/min/1.73 m2) than in those without OH (61.1 ± 15.9 mL/min/1.73 m2) (p < 0.05). A greater fall in SBP at 0-min (12.8 ± 6.3 vs. 7.7 ± 3.2 mmHg) and at 1-min (8.4 ± 4.5 vs. 5.7 ± 2.8 mmHg) was found in CKD patients in respect to patients without CKD during active standing test (p < 0.05). Similarly, a DBP reduction at 0-min and at 1-min was observed in CKD patients in respect to patients without CKD (p < 0.05). A multivariate logistic regression analysis showed that CKD was associated to OH (OR 2.426; 95%CI 1.192-4.937; p = 0.014).

CONCLUSIONS

CKD is associated to OH in hospitalised older adults.

Resting strain analysis to identify myocardial ischemia in patients with advanced chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) is associated with higher incidence of cardiovascular death. Screening for coronary artery disease in asymptomatic or mildly symptomatic patients is challenging.

OBJECTIVE

The aim of this study was to investigate the incremental value of resting deformation analysis in predicting positive results for myocardial ischemia during stress transthoracic echocardiography in patients with end-stage CKD.

METHODS

Sixty-one patients (mean age: 62.3 ± 11.8, 65.7% men) with end-stage CKD were included in the study. Patients underwent a resting transthoracic echocardiogram and a dobutamine stress contrast echo (DSE) protocol. Positive results of DSE were defined as stress-induced left ventricular (LV) wall motion abnormalities.

RESULTS

The study cohort had normal or mildly impaired systolic function: mean LV ejection fraction (EF) was 49.2% (±10.4) and mean LV global longitudinal strain (GLS) was 14.4% (±4.5). Half of our population had impaired left atrial (LA) strain: mean LA reservoir, conduit, and contractile reserve were 24.1% (±12.6), 10.6% (±5.9), and 13.6% (±9.2), respectively. DSE was positive for ischemia in 55.7%. A significant negative association with DSE results was found for LV EF, LV GLS and the conduit phase of LA strain. Both LV and LA dimensions showed positive correlation with presence of ischemia in DSE. Multivariate logistic regression analysis showed that LV GLS was independently associated with DSE (p = 0.007), after controlling for covariates, with high diagnostic accuracy.

CONCLUSION

Resting LV deformation could predict positive results during DSE, thus may be useful to better identify renal patients who might benefit from coronary artery screening.

Chronic Renal Failure and Cardiovascular Disease: A Comprehensive Appraisal

Coronary artery disease is highly prevalent in patients with chronic kidney disease. The concomitant renal disease often poses a major challenge in decision making as symptoms, cardiac biomarkers and noninvasive studies for evaluation of myocardial ischemia have different sensitivity and specificity thresholds in this specific population. Moreover, the effectiveness and safety of intervention and medical treatment in those patients is of great doubt as most clinical studies exclude patients with advance CKD. In the present paper, we discuss and review the literature in the diagnosis, treatment and prevention of CAD in the acute and chronic setting, in patients with CKD.

The significance of electrocardiographic changes without echocardiographic evidence of segmental wall motion abnormalities in patients undergoing dobutamine stress echocardiography

Ischemic ECG changes during dobutamine stress echocardiography (DSE) have been reported to have low sensitivity and specificity for detecting myocardial ischemia in the absence of wall motion abnormalities on echocardiography. We present a case of a renal transplant candidate with severe multivessel disease who had ST depressions without any wall motion abnormalities on DSE. Certain studies have shown the sensitivity of DSE is lower in patients with left ventricular hypertrophy and/or end stage renal disease, but the significance of ischemic ECG changes with no evidence of wall motion abnormalities in these patients has not been well studied.

Orthostatic Hypotension in Asymptomatic Patients with Chronic Kidney Disease

Background and objective: Orthostatic hypotension (OH) is a decrease in systolic blood pressure (BP) of 20 mm Hg and in diastolic BP of 10 mm Hg when changing the position from lying to standing. Arterial hypertension (AH), comorbidities and polypharmacy contribute to its development. The aim was to assess the presence of OH and its predictors in asymptomatic chronic kidney disease (CKD) patients. Material and methods: 45 CKD patients with estimated glomerular filtration rate (eGFR) ≤ 60 mL/min/1.73 m² (CKD+) were examined for signs of OH and its predictors. The results were compared with the control group of 22 patients with eGFR > 60 mL/min/1.73 m² (CKD-). Asymptomatic patients without ischemic heart disease and previous stroke were qualified. Total blood count, serum creatinine, eGFR, urea, phosphates, calcium, albumins, parathyroid hormone, uric acid, C reactive protein, N-terminal pro b-type natriuretic peptide, lipid profile, and urine protein to creatinine ratio were assessed. Simultaneously, patients underwent echocardiography. To detect OH, a modified Schellong test was performed. Results: OH was diagnosed in 17 out of 45 CKD+ patients (average age 69.12 ± 13.2) and in 8 out of 22 CKD- patients (average age 60.50 ± 14.99). The CKD+ group demonstrated significant differences on average values of systolic and diastolic BP between OH+ and OH- patients, lower when standing. In the eGFR range of 30-60 mL/min/1.73 m² correlation was revealed between OH and β-blockers (p = 0.04), in the entire CKD+ group between β-blockers combined with diuretics (p = 0.007) and ACE-I (p = 0.033). Logistic regression test revealed that chronic heart failure (CHF, OR = 15.31), treatment with β-blockers (OR = 13.86) were significant factors influencing the presence of OH. Conclusions: Predictors of OH in CKD may include: CHF, treatment with β-blockers, combined with ACE-I and diuretics.

NT-proBNP in the Prognosis of Death or Need for Renal Replacement Therapy in Patients with Stage 3-5 Chronic Kidney Disease

BACKGROUND

The risk of cardiovascular (CV) complications is much greater in patients with chronic kidney disease (CKD). The aim of this study was to assess predictors of mortality, renal failure progression, and the need for dialysis in patients with CKD.

METHODS

The study group consisted of 70 patients with stage 3-5 CKD, followed up on average for 33.4 ± 15.6 months. Laboratory tests and echocardiography were performed on all patients. Composite endpoints were defined as (1) all-cause mortality and (2) mortality or renal replacement therapy (RRT), defined as the initiation of dialysis therapy.

RESULTS

During the observation period, 13 patients died and 11 began dialysis therapy. NT-proBNP was found to be a significant predictor in receiver operating characteristic curve analysis for all study endpoints. The optimal cutoff value for NT-proBNP as a predictor of mortality was 569.8 pg/mL, with a sensitivity of 53.8% and a specificity of 89.1%. For mortality or RRT, the cutoff value for NT-proBNP was 384.9 pg/mL, with a sensitivity and specificity of 70.8 and 72.7%, respectively. In a multivariate regression analysis, NT-proBNP was an independent predictor of mortality with an OR = 7.5 (95% CI: 1.05-53.87; p = 0.044) and of mortality or RRT with an OR = 4.7 (95% CI: 1.01-22.66; p = 0.048).

CONCLUSIONS

NT-proBNP is an independent predictor of mortality in patients with CKD and can also be useful for CV risk stratification in this patient population.

Asymptomatic myocardial ischemia forecasts adverse events in cardiovascular magnetic resonance dobutamine stress testing of high-risk middle-aged and elderly individuals

BACKGROUND

Current guidelines for assessing the risk of experiencing a hospitalized cardiovascular (CV) event discourage stress testing of asymptomatic individuals; however, these recommendations are based on evidence gathered primarily from those aged < 60 years, and do not address the possibility of unrecognized "silent myocardial ischemia" in middle aged and older adults.

METHODS

We performed dobutamine cardiovascular magnetic resonance (CMR) stress testing in 327 consecutively recruited participants aged > 55 years without CV-related symptoms nor known coronary artery disease, but otherwise at increased risk for a future CV event due to pre-existing hypertension or diabetes mellitus for at least 5 years. After adjusting for the demographics and CV risk factors, log-rank test and Cox proportional hazards models determined the additional predictive value of the stress test results for forecasting hospitalized CV events/survival. Either stress-induced LV wall motion abnormalities or perfusion defects were used to indicate myocardial ischemia.

RESULTS

Participants averaged 68 ± 8 years in age; 39% men, 75% Caucasian. There were 38 hospitalized CV events or deaths which occurred during a mean follow-up of 58 months. Using Kaplan-Meier analyses, myocardial ischemia identified future CV events/survival (p <  0.001), but this finding was more evident in men (p <  0.001) versus women (p = 0.27). The crude hazard ratio (HR) of myocardial ischemia for CV events/survival was 3.13 (95% CI: 1.64-5.93; p < 0.001). After accounting for baseline demographics, CV risk factors, and left ventricular ejection fraction/mass, myocardial ischemia continued to be associated with CV events/survival [HR: 4.07 (95% CI: 1.95-8.73) p < 0.001].

CONCLUSIONS

Among asymptomatic middle-aged individuals with risk factors for a sentinel CV event, the presence of myocardial ischemia during dobutamine CMR testing forecasted a future hospitalized CV event or death. Further studies are needed in middle aged and older individuals to more accurately characterize the prevalence, significance, and management of asymptomatic myocardial ischemia.

TRIAL REGISTRATION

( ClinicalTrials.gov identifier): NCT00542503 and was retrospectively registered on October 11th, 2007.