Jiun-Chi Huang

Framingham Risk Score with Cardiovascular Events in Chronic Kidney Disease

The Framingham Risk Score (FRS) was developed to predict coronary heart disease in various populations, and it tended to under-estimate the risk in chronic kidney disease (CKD) patients. Our objectives were to determine whether FRS was associated with cardiovascular events, and to evaluate the role of new risk markers and echocardiographic parameters when they were added to a FRS model. This study enrolled 439 CKD patients. The FRS is used to identify individuals categorically as “low” (<10% of 10-year risk), “intermediate” (10–20% risk) or “high” risk (≧ 20% risk). A significant improvement in model prediction was based on the −2 log likelihood ratio statistic and c-statistic. “High” risk (v.s. “low” risk) predicts cardiovascular events either without (hazard ratios [HR] 2.090, 95% confidence interval [CI] 1.144 to 3.818) or with adjustment for clinical, biochemical and echocardiographic parameters (HR 1.924, 95% CI 1.008 to 3.673). Besides, the addition of albumin, hemoglobin, estimated glomerular filtration rate, proteinuria, left atrial diameter >4.7 cm, left ventricular hypertrophy or left ventricular ejection fraction<50% to the FRS model significantly improves the predictive values for cardiovascular events. In CKD patients, “high” risk categorized by FRS predicts cardiovascular events. Novel biomarkers and echocardiographic parameters provide additional predictive values for cardiovascular events. Future study is needed to assess whether risk assessment enhanced by using these biomarkers and echocardiographic parameters might contribute to more effective prediction and better care for patients.

The ratio of observed to predicted left ventricular mass is independently associated with increased cardiovascular events in patients with chronic kidney disease.

A condition involving the growth of the myocardium that exceeds hemodynamic needs has been reported and called as inappropriate left ventricular mass (LVM). The appropriateness of LVM can be estimated by the ratio of observed LVM to predicted LVM. The excessive growth of LVM is frequently noted in patients with chronic kidney disease (CKD). This study is designed to assess whether the ratio of observed to predicted LVM is a useful prognostic indicator of cardiovascular events in patients with moderate to advanced CKD. We consecutively enrolled 485 patients with CKD stages 3–5 from our Outpatient Department of Internal Medicine. Inappropriate LVM was defined as observed LVM more than 28% greater than the predicted value. The relative risk of cardiovascular events was analyzed by Cox-regression methods. There was a significant trend for a stepwise increase in the observed/predicted LVM ratio (P<0.001) and the prevalence of inappropriate LVM (P=0.003) corresponding to advances in CKD stages. In the multivariate analysis, old age, a history of coronary artery disease, congestive heart failure, atrial fibrillation, wide pulse pressure, decreased serum albumin and hemoglobin levels, left atrial diameter >4.7 cm and increased observed/predicted LVM were independently associated with increased cardiovascular events. Our findings show that increased observed/predicted LVM is independently associated with adverse cardiovascular outcomes in patients with CKD stages 3–5.

Body mass index, mortality, and gender difference in advanced chronic kidney disease.

Background and Aim A higher body mass index (BMI) appears to be reversely associated with mortality in dialysis patients. Moreover, although women have better survival in chronic kidney disease (CKD), this survival advantage is cancelled in dialysis. The association between BMI and mortality and the gender difference remain controversial in advanced CKD. Methods This study enrolled 3,320 patients (1,938 men and 1,382 women) from southern Taiwan who had CKD stages 3–5 with a BMI of 15.0–35.0 kg/m2. Results During a median 2.9-year follow-up, there were 328 (16.9%) all-cause mortality and 319 (16.5%) cardiovascular (CV) events and death in male patients, 213 (15.4%) all-cause mortality and 224 (16.2%) CV events and death in female patients. Compared with the reference BMI of 27.6–30.0 kg/m2 in an adjusted Cox model, lower-BMI groups in men, BMI 15.0–20.0 kg/m2 and 20.1–22.5 kg/m2, were associated with higher risks of all-cause mortality: hazard ratios (HRs) 3.19 (95% confidence interval [CI], 1.97–5.18) and 2.01 (95% CI, 1.29–3.14), respectively. Higher-BMI group in men, BMI 30.1–35.0 kg/m2, was associated with a higher risk of all-cause mortality: HR 1.72 (95% CI, 1.02–2.96). Likewise, lower- and higher-BMI groups in men were associated with a higher risk of CV events and death. In women, these associations between BMI and poor outcomes were not observed. Conclusions In advanced CKD, there was a reverse J-shaped association between BMI and all-cause mortality, and a U-shaped association between BMI and CV outcomes in men. Neutral associations between BMI and poor outcomes were detected in women. Gender could modify the effect of BMI on mortality in patients with CKD.

Anemia and Left Ventricular Hypertrophy With Renal Function Decline and Cardiovascular Events in Chronic Kidney Disease

Background:Anemia is a common complication in patients with chronic kidney disease (CKD), which may initiate or accelerate left ventricular hypertrophy (LVH). This study is designed to assess whether the coexistence of anemia and LVH is independently associated with the rate of renal function decline and increased cardiovascular events in patients with CKD stages 3 to 5. Methods:This longitudinal study enrolled 415 patients, who were classified into 4 groups according to sex-specific median values of hemoglobin and with/without LVH. The change in renal function was measured by estimated glomerular filtration rate slope. Cardiovascular events were defined as cardiovascular death, hospitalization for unstable angina, nonfatal myocardial infarction, sustained ventricular arrhythmia, hospitalization for congestive heart failure, transient ischemia attack, and stroke. The relative risk of cardiovascular events was analyzed by Cox’s regression method. Results:The estimated glomerular filtration rate slope was significantly lower in the group with lower hemoglobin and LVH than in the other groups (P ⩽ 0.031). In addition, patients with lower hemoglobin and LVH were independently associated with increased cardiovascular events (hazard ratio, 4.269; 95% confidence interval, 1.402–13.000; P = 0.011). Conclusions:Our findings showed that the coexistence of anemia and LVH was independently associated with faster renal function decline and poor cardiovascular outcomes in patients with CKD. Assessments of serum hemoglobin level and LVH by echocardiography may help identify a high-risk group of poor renal and cardiovascular prognosis in patients with CKD stages 3 to 5.

Ratio of transmitral E-wave velocity to early diastole mitral annulus velocity with cardiovascular and renal outcomes in chronic kidney disease.

Background/Aims: Impaired left ventricular diastolic function and increased left ventricular filling pressure are frequently noted in patients with chronic kidney disease (CKD), even in early stages. The association of increased left ventricular filling pressure with cardiovascular and renal outcomes remains uncertain in CKD. This study is designed to assess whether the ratio of transmitral E-wave velocity (E) to early diastole mitral velocity (Ea) is associated with cardiovascular events and progression to dialysis in patients with CKD stages 3-5. Methods: This longitudinal study enrolled 356 predialysis CKD patients. Cardiovascular events were defined as cardiovascular death, hospitalization for unstable angina, nonfatal myocardial infarction, ventricular tachycardia, hospitalization for congestive heart failure, transient ischemia attack, and stroke. The renal endpoint was defined as commencement of dialysis. The relative cardiovascular events and renal endpoints risks were analyzed by Cox regression methods. Results: The high E/Ea was independently associated with old age, cerebrovascular disease, congestive heart failure, high systolic blood pressure, hypertriglyceridemia, low hemoglobin, proteinuria, and worse echocardiographic profiles. Besides, the high E/Ea increased the risk of cardiovascular events (hazard ratio (HR) 1.067; 95% confidence interval (CI) 1.017-1.119; p = 0.008) and progression to dialysis (HR 1.042; 95% CI 1.000-1.085; p = 0.048). Conclusions: Our study in patients of CKD stages 3-5 demonstrated the high E/Ea was associated with increased cardiovascular events and progression to dialysis. Assessment of the E/Ea by Doppler echocardiography is useful for predicting the risk of adverse cardiovascular and renal outcomes in CKD patients.

Performance of the Framingham risk score in patients receiving hemodialysis.

The Framingham Risk Score (FRS), calculated by considering conventional risk factors of cardiovascular diseases, was developed to predict coronary heart disease in various populations. However, reverse epidemiology has been raised concerning these risk factors in predicting high cardiovascular mortality in hemodialysis patients. Our objectives are to determine whether FRS is associated with overall and cardiovascular mortality and the role of new risk markers when they were added to a FRS model in hemodialysis patients.

Lethal cardiac arrhythmia during central venous catheterization in a uremic patient: A case report and review of the literature

Double‐lumen central venous catheter (CVC) is a rapid access technique for hemodialysis (HD) when an arteriovenous fistula or graft is not available. A variety of procedure‐related complications have been reported, such as infection and pneumothorax, but serious cardiac complications are relatively less mentioned. We report a uremic woman with preexisting left bundle branch block who required emergent HD and received jugular double‐lumen CVC insertion, which was complicated by short‐duration ventricular tachycardia followed by complete atrio‐ventricular block and bradycardia. Pharmacological management did not reverse heart rate and rhythm. External pacing was not applied because she remained hemodynamically stable in the course of HD. Heart rate returned to sinus rhythm with left bundle branch block 4 hours later and did not recur through the whole admission period. We speculate that the transient arrhythmia might have been induced by mechanical contact with the ventricular wall during the procedure with the guided metallic wire. In conclusion, physicians responsible for CVC catheterization should pay more attention to patients with preexisting cardiac arrhythmia to prevent such technical mistakes from transpiring.

Association of P-Wave Dispersion with Overall and Cardiovascular Mortality in Hemodialysis Patients

Background/Aims: The P-wave parameters that are measured using a 12-lead electrocardiogram are commonly used as noninvasive tools for assessing left atrial enlargement. This study was designed to assess whether P-wave dispersion is associated with overall and cardiovascular mortality in hemodialysis patients. Methods: This study enrolled 209 hemodialysis patients. We measured the P-wave dispersion corrected by heart rate, that is, the corrected P-wave dispersion (PWdisperC), and assessed its correlation with overall and cardiovascular mortalities. Results: The mean PWdisperC of all the patients was 93.3 ± 21.1 ms. During the follow-up period (mean 5.4 years), 58 deaths and 37 cardiovascular deaths were recorded. The adjusted value of PWdisperC was also associated with overall (hazards ratio (HR) 1.018, 95% CI 1.004-1.033, p = 0.014) and cardiovascular (HR 1.032, 95% CI 1.012-1.053, p = 0.002) mortalities. Multivariate Cox regression analysis identified tertile 3 of PWdisperC (vs. tertile 1) to be associated with overall (HR 2.472, 95% CI 1.181-5.174, p = 0.016) and cardiovascular (HR 3.896, 95% CI 1.463-10.376, p = 0.007) mortalities, after adjustment for demographic, clinical and biochemical parameters. Adding PWdisperC to a model of clinical features could significantly improve the predictive value for overall (p = 0.044) and cardiovascular (p = 0.002) mortalities. Conclusions: We concluded that PWdisperC was positively associated with overall and cardiovascular mortalities in hemodialysis patients and could provide additional prognostic values. Screening hemodialysis patients by using PWdisperC may facilitate identifying a group of patients with poor prognosis.

Heart Rate Variability Change Before and After Hemodialysis is Associated with Overall and Cardiovascular Mortality in Hemodialysis

Low heart rate variability (HRV) has been recognized to correlate with adverse cardiovascular (CV) outcomes in hemodialysis (HD) patients. It has been reported that HRV might be improved after HD, but whether the improved HRV after HD predicts a better CV prognosis remains to be determined. This study examined the ability of the change in HRV before and after HD in predicting overall and CV mortality in HD patients. This study enrolled 182 patients under maintenance HD. HRV was examined to assess changes before and after HD. The change in HRV (ΔHRV) was defined as post-HD HRV minus pre-HD HRV. During a median follow-up period of 35.2 months, 29 deaths (15.9%) were recorded. Multivariate analysis showed that decreased ΔLF% was associated with increased overall (hazard ratios [HR], 0.978; 95% confidence interval [CI], 0.961–0.996; p = 0.019) and CV mortality (HR, 0.941; 95% CI, 0.914–0.970; p < 0.001), respectively. Moreover, adding ΔLF% to a clinical model provided an additional benefit in the prediction of overall (p = 0.002) and CV mortality (p < 0.001). HRV change before and after HD (ΔHRV) is an useful clinical marker, and it is stronger than HRV before HD in predicting overall and CV mortality.

Link between Peripheral Artery Disease and Heart Rate Variability in Hemodialysis Patients

Peripheral artery disease (PAD) and low heart rate variability (HRV) are highly prevalent in hemodialysis patients, and both are associated with increased cardiovascular morbidity and mortality. This study aims to examine the suggested relationship between PAD and HRV, and the relationship of parameters before and after hemodialysis. This study enrolled 161 maintenance hemodialysis patients. PAD was defined as ABI < 0.9 in either leg. HRV was performed to assess changes before and after hemodialysis. The change in HRV (△HRV) was defined as post-hemodialysis HRV minus pre-hemodialysis HRV. Patients’ clinical parameters were collected from the dialysis records. All HRV parameters except high frequency (HF) % were lower in patients with PAD than patients without PAD, though not achieving significant level. In patients without PAD, HF (P = 0.013), low frequency (LF) % (P = 0.028) and LF/HF (P = 0.034) were significantly elevated after hemodialysis, whereas no significant HRV parameters change was noted in patients with PAD. Serum intact parathyroid hormone was independently associated with △HF (β = -0.970, P = 0.032) and △LF% (β = -12.609, P = 0.049). Uric acid level (β = -0.154, P = 0.027) was negatively associated with △LF/HF in patients without PAD. Our results demonstrated that some of the HRV parameters were significantly increased after hemodialysis in patients without PAD, but not in patients with PAD, reflecting a state of impaired sympatho-vagal equilibrium. Severity of secondary hyperparathyroidism and hyperuricemia contributed to lesser HRV parameters increase after hemodialysis in patients without PAD.