Impact of hemodialysis on local vessel healing and thrombus formation after drug-eluting stent implantation

Incidence of Acute Thrombotic Occlusion and Its Predictors After Contemporary Femoropopliteal Endovascular Therapy in Patients With Peripheral Artery Disease

PURPOSE

This study investigated the incidence of acute thrombotic occlusion (ATO) and its predictors after contemporary femoropopliteal (FP) endovascular therapy (EVT) for peripheral artery disease.

MATERIALS AND METHODS

We retrospectively examined 763 limbs (chronic limb-threatening ischemia [CLTI]: 44%, involving popliteal lesion: 44%) in 644 patients (mean age: 75±9 years, male: 71%, hemodialysis: 34%) who successfully underwent EVT with contemporary FP devices (drug-coated stent: n=220, stent graft: n=158, drug-eluting stent: n=150, drug-coated balloon [DCB]: n=235) from June 2012 to July 2020. The outcome measure was ATO defined as acute onset of claudication and/or signs of CLTI in combination with angiographic evidence of occlusive thrombus formation within the treated segment. Cox proportional hazards regression models were used to identify baseline characteristics associated with the incidence of ATO after EVT treated with scaffold. To determine the impact of ATO occurrence and creatine phosphokinase (CPK) elevation on the subsequent composite outcome of mortality or major amputation, we developed the Cox model in which the trichotomous variable (free from ATO, ATO without CPK elevation, and ATO with CPK elevation) was a time-dependent covariate.

RESULTS

The 24-month incidence of ATO in the overall population was 4.3%±0.8% (DCB: 1.0%±0.7% vs scaffold: 5.8%±1.1%, p<0.01). Hemodialysis (hazard ratio [HR]: 2.63, p=0.02) and involving popliteal lesion (HR: 8.22, p<0.01) were independently associated with an increased risk of ATO in patients treated with scaffold. Both ATO without CPK elevation and ATO with CPK elevation were significantly associated with a composite outcome of mortality or major amputation comparing free from ATO, with an HR of 2.39 and 9.87, respectively (p=0.02 and p<0.01).

CONCLUSION

We found a substantial incidence of ATO after contemporary FP-EVT, particularly with scaffold. Hemodialysis and involving popliteal lesion were significantly associated with ATO risk in patients treated with scaffold. The occurrence of ATO, particularly with CPK elevation, was associated with an increased risk of a subsequent composite outcome of mortality or major amputation. The scaffold was safely used in patients without those risk factors of ATO, but a non-scaffolding strategy should be considered for patients with more risk factors.

CLINICAL IMPACT

The scaffold was safely used in patients without hemodialysis and involving popliteal lesion, but a non-scaffolding strategy should be considered for patients with those risk factors. The occurrence of ATO, particulary with CPK elevation, was of high risk of mortality or amputation.

Drug-coated balloons versus drug-eluting stents for coronary de novo lesions in dialysis patients

BACKGROUND

The aim of this study was to compare the efficacy of drug-coated balloon (DCB) angioplasty with drug-eluting stent (DES) angioplasty in the treatment of de novo coronary artery lesions in dialysis patients.

METHOD

We retrospectively enrolled 400 consecutive dialysis patients with 464 coronary de novo lesions treated by DCB or DES from five participating institutions in Japan. The primary endpoint was target lesion revascularization (TLR) at 12 months. We performed serial coronary angiographic analysis.

RESULTS

There were no significant differences in the rate of TLR between the groups in either crude or propensity score-matched analysis (DES 14.1% vs. DCB 14.7%, P = 0.864, DES 12.1% vs. 12.1%, P = 1.00). Target lesion thrombosis was not observed in the DCB group; however, stent thrombosis was observed in 7 patients (2.2%) in the DES group. The rate of binary restenosis was similar in both groups (DES, 20.9% vs. DCB, 22.8%; P = 0.749). The late lumen loss at follow-up was significantly greater in the DES group than in the DCB group (0.61 ± 0.76 mm vs 0.22 ± 0.48 mm; P < 0.001). Late lumen enlargement was observed in 38.6% of patients in the DCB group.

CONCLUSION

The efficacy of DCB angioplasty for de novo coronary artery lesions in dialysis patients was similar to that of DES angioplasty in the real world. Drug-coated balloon angioplasty can be an acceptable treatment for de novo coronary artery lesions in dialysis patients.

Formation of Calcified Nodule as a Cause of Early In-Stent Restenosis in Patients Undergoing Dialysis

Background Dialysis is an independent risk factor for in-stent restenosis (ISR) after stent implantation in coronary arteries. However, the characteristics of ISR in patients undergoing dialysis remain unclear, as there are no histological studies evaluating the causes of this condition. The aim of the present study was to investigate the causes of ISR between patients who are undergoing dialysis and those who are not by evaluating tissues obtained from ISR lesions using directional coronary atherectomy. Methods and Results A total of 29 ISR lesions from 29 patients included in a multicenter directional coronary atherectomy registry of 128 patients were selected for analysis and divided into a dialysis group (n=8) and a nondialysis group (n=21). Histopathological evaluation demonstrated that an in-stent calcified nodule was a major histological characteristic of ISR lesions in the dialysis group and the prevalence of an in-stent calcified nodule was significantly higher in the dialysis group compared with the nondialysis group (75% versus 5%, respectively; P<0.01). On the other hand, the prevalence of an in-stent lipid-rich plaque was significantly lower in the dialysis group compared with the nondialysis group (0% versus 43%, respectively; P=0.03). In all cases with an in-stent calcified nodule, the underlying calcification before stent implantation was moderate to severe. When tissue characteristics were stratified according to duration post-stent implantation, an in-stent calcified nodule in the dialysis group was mainly observed within 1 year after stent implantation. Conclusions In-stent calcified nodules are a common cause of ISR in patients undergoing dialysis and are observed within 1 year after stent implantation, suggesting different causes of ISR between patients undergoing dialysis and those who are not.

CKD Increases Carbonylation of HDL and Is Associated with Impaired Antiaggregant Properties

BACKGROUND

CKD is associated with increased oxidative stress that correlates with occurrence of cardiovascular events. Modifications induced by increased oxidative stress particularly affect circulating lipoproteins such as HDL that exhibit antiatheromatous and antithrombotic properties in vitro.

METHODS

To explore the specific role of oxidative modifications of HDL in CKD and their effect on the platelet-targeting antiaggregant properties of HDL, we used a CKD (5/6 nephrectomy) rabbit model. For ex vivo assessment of the antiaggregant properties of HDL, we collected blood samples from 15 healthy volunteers, 25 patients on hemodialysis, and 20 on peritoneal dialysis. We analyzed malondialdehyde, 4-hydroxynonenal (HNE), and 4-hydroxy-2-hexenal protein adduct levels. Platelet aggregation and activation were assessed by aggregometry, thromboxane B2 assay, or FACS. We modified HDL from controls by incubating it overnight at 37°C with 100 µM of HNE.

RESULTS

HDL from CKD rabbits and patients on hemodialysis had HNE adducts. The percentage of platelet aggregation or activation induced by collagen was significantly higher when platelets were incubated with HDL from CKD rabbit and hemodialysis groups than with HDL from the control group. In both rabbits and humans, platelet aggregation and activation were significantly higher in the presence of HNE-modified HDL than with HDL from their respective controls. Incubation of platelets with a blocking antibody directed against CD36 or with a pharmacologic inhibitor of SRC kinases restored the antiaggregative phenotype in the presence of HDL from CKD rabbits, patients on hemodialysis and peritoneal dialysis, and HNE-modified HDL.

CONCLUSIONS

HDL from CKD rabbits and patients on hemodialysis exhibited an impaired ability to inhibit platelet aggregation, suggesting that altered HDL properties may contribute to the increased cardiovascular risk in this population.

Effect of Hemodialysis on 7-Year Clinical Outcomes After Sirolimus-Eluting Stent Implantation

BACKGROUND

Hemodialysis (HD) patients are reported to show poor clinical outcomes after percutaneous coronary intervention (PCI) with sirolimus-eluting stent (SES) compared with non-HD patients and their long-term prognosis remains unclear.

METHODS AND RESULTS

We prospectively enrolled 489 consecutive patients undergoing PCI with SES and performed a retrospective analysis focusing on HD patients. Median follow-up was 7.0 years (interquartile range, 4.2-7.9) and the follow-up rate was 100%. At the 7-year follow-up, the cumulative incidences of all-cause death, target lesion revascularization (TLR) and major adverse cardiac events (MACE) were significantly higher in HD patients than in non-HD patients (HD vs. non-HD=34.7% vs. 9.6%, 42.6% vs. 10.2% and 75.3% vs. 24.4%, respectively; log-rank P<0.001). Cox-proportional hazard analysis revealed that independent predictors of all-cause death were HD (hazard ratio [HR] 2.88, 95% confidence interval [CI]: 1.39-6.00), insulin-treated diabetes mellitus (HR 2.19, 95% CI: 1.17-4.11), heart failure (HR 2.58, 95% CI: 1.25-5.32) and older age (HR 1.06/1-age, 95% CI: 1.02-1.10). Moreover, HD was an independent predictor of TLR (HR 3.63, 95% CI: 1.85-7.11) and MACE (HR 3.54, 95% CI: 2.19-5.73).

CONCLUSIONS

In the present study, Japanese HD patients undergoing PCI with SES showed poorer long-term clinical outcomes than non-HD patients. HD was a strong predictor of long-term adverse events after SES implantation.

Impact of residual platelet reactivity under clopidogrel treatment for lesions and the clinical outcome after drug-eluting stent implantation in patients with hemodialysis

BACKGROUND

Hemodialysis (HD) patients are at high risk for adverse clinical outcomes after drug-eluting stent (DES) implantation. However, the impact of residual platelet reactivity under dual anti-platelet therapy in this subset of patients remains unclear.

METHODS

We enrolled 142 stable angina patients (194 lesions) treated with DES, who were taking aspirin and 75mg clopidogrel and had undergone 8-month angiography with optical coherence tomography (OCT). OCT findings and major adverse cardiac events (MACEs) at 1 year (cardiac death, acute coronary syndrome, target lesion and vessel revascularization, and stent thrombosis) were compared between 28 HD patients and 114 non-HD patients. Responsiveness to clopidogrel was assessed by measuring P2Y12 reaction unit (PRU) at 8 months.

RESULTS

PRU was significantly higher in HD patients than in non-HD patients (p=0.006), even though proportion of cytochrome P450 2C19 genotype was equivalent. HD patients had a significantly higher rate of thrombi formation (assessed using OCT) and MACEs than non-HD patients (thrombi: p=0.001; MACEs: p=0.0001). The PRU value was independently associated with MACEs in both groups. The optimal cutoff values of PRU for predicting MACEs were 235 for HD patients and 259 for non-HD patients.

CONCLUSIONS

HD was associated with a high residual platelet reactivity, which may contribute to the higher incidence of MACEs after DES implantation in HD patients. HD may be a patient profile that merits a more potent anti-platelet regimen.