Project description:BackgroundStent thrombosis (ST) is a rare, but potentially fatal complication. Procedural problems, such as stent under-dimension/under-expansion or dual antiplatelet drug resistance may result into ST. These conditions are more frequent during primary percutaneous coronary intervention for ST-elevation myocardial infarction (STEMI).Case summaryA 60-year-old male patient presented to our hospital with an inferior STEMI. In the emergency department, a dual antiplatelet therapy was administered with ticagrelor 180 mg and aspirin 250 mg IV. During the observation, the patient experienced a ventricular fibrillation. Urgent coronary angiography showed an occlusion of the proximal right coronary artery. Thrombus aspiration was performed followed by implantation of one drug-eluting stent. After 45 min early ST occurred and was treated by immediate thrombus aspiration and post-dilatation. Intravascular ultrasound sonography (IVUS) showed severe strut malapposition due to a partial crush after post-dilatation. Since it was not possible to directly insert the first guidewire in the stent lumen, the IVUS probe was placed between the vessel wall and the crushed stent to guide the manoeuvre.DiscussionCrushed stent is a rare complication, being caused by an incorrect passage of the guidewire between the stent's struts and the vessel wall in case of severe underexpansion. In this case, an IVUS-guided re-entry could be an option to gain the stent true lumen and avoid a second stent implantation.
Project description:Despite the benefits of successful percutaneous coronary interventions (PCIs) for chronic total occlusion (CTO) lesions, PCIs of CTO lesions still carry a high rate of adverse events, including in-stent restenosis (ISR). Because previous reports have not specifically investigated the intravascular ultrasound (IVUS) predictors of ISR in CTO lesions, we focused on these predictors. We included 126 patients who underwent successful PCIs, using drug-eluting stents, and post-PCI IVUS of CTO lesions. Patient and lesion characteristics were analyzed to elucidate the ISR predictors. In each lesion, an average of 1.7 ± 0.7 (mean length, 46.4 ± 20.3 mm) stents were used. At 9 months follow-up, 14 (11%) patients demonstrated ISR, and 8 (6.3%) underwent target lesion revascularization. Multivariate logistic regression analysis showed that the independent predictors of ISR were the post-PCI minimal luminal diameter (MLD) and the stent expansion ratio (SER; minimal stent cross-sectional area (CSA) over the nominal CSA of the implanted stent), measured using quantitative coronary angiography (QCA) and IVUS, respectively. A receiver operating characteristic analysis indicated that the best post-PCI MLD and SER cut-off values for predicting ISR were 2.4 mm (area under the curve [AUC], 0.762; 95% confidence interval (CI), 0.639-0.885) and 70% (AUC, 0.714; 95% CI, 0.577-0.852), respectively. Lesions with post-PCI MLD and SER values less than these threshold values were at a higher risk of ISR, with an odds ratio of 23.3 (95% CI, 2.74-198.08), compared with lesions having larger MLD and SER values. Thus, the potential predictors of ISR, after PCI of CTO lesions, are the post-PCI MLD and SER values. The ISR rate was highest in lesions with a post-PCI MLD ≤2.4 mm and an SER ≤70%.
Project description:BackgroundIatrogenic aortocoronary dissection (ACD) is a rare but potentially devastating complication of cardiac catheterization. We describe a case of an iatrogenic ACD following catheter engagement and balloon inflation of the proximal right coronary artery (RCA) during an elective percutaneous coronary intervention (PCI).Case summaryAn 81-year-old woman presented with an acute inferior wall ST-elevation myocardial infarction. Emergent coronary angiography revealed the three-vessel diseases. Primary PCI for the culprit lesion of the occluded mid-circumflex artery was successfully performed. After 10 days, an elective PCI for the residual RCA lesions was performed. After the balloon inflation of the proximal RCA, iatrogenic ACD was detected. Intravascular ultrasound-guided stent implantation sealing an entry tear prevented further dissection. The post-operative course was uneventful, and the patient was discharged 1 week later. Follow-up cardiac computed tomography revealed a disappearance of the aortocoronary intramural haematoma.DiscussionThis case emphasizes the importance of prompt detection and intervention for iatrogenic ACD. Heart team discussion is essential to determine whether cardiovascular surgery or percutaneous management should be performed. Bail-out stent implantation sealing an entry tear is frequently used and effective, and an intravascular ultrasound system would help to recognize the morphology of ACD, contributing to the safe procedure.
Project description:BACKGROUND:Ureteroarterial fistula is a rare life-threatening complication of indwelling ureteral stents. The mechanism has not yet been fully evaluated using intravascular imaging. CASE PRESENTATION:An-84-year-old female was referred to our unit because of large volume pulsatile bleeding from the left ureter during routine stent exchange in the urology department. The hematuria was initially managed by rapidly exchanging for a new stent; however, the patient went into hypovolemic shock due to acute blood loss. The patient underwent implantation of the bilateral ureteral stents due to urinary retention caused by retroperitoneal fibrosis 2 years ago. To prevent ureteral infection, occlusion of the stents and stone formation, the stents were exchanged every 6 months. Computed tomography revealed contact between the left ureter and the common iliac artery. Therefore, ureteroarterial fistula was suspected and endovascular therapy was performed. Although angiography did not show definite blood flow into the ureter, a soft guidewire was advanced from the subintima of the external iliac artery to the left ureter. The diagnosis of ureteroarterial fistula was confirmed. Intravascular ultrasound identified the stent in the ureter and its connection to the subintima of the external iliac artery. The ureter did not contact directly to the inner lumen of the iliac arteries according to the ultrasound findings; therefore, we considered that the risk of stent-graft infection might not be high. After coil embolization of the ipsilateral internal iliac artery, a covered stent was implanted in the external iliac artery to seal the subintimal entry. The patient had no further episodes of any gross hematuria on dual anti-platelet therapy, when the ureteral stent was exchanged three time during 1 year after the endovascular therapy. CONCLUSIONS:We demonstrated a case of ureteroarterial fistula, in which intravascular ultrasound allowed to visualize the communication between the ureter and the subintimal lumen in the external iliac artery.
Project description:IntroductionPrevious studies have demonstrated the feasibility of bedside placement of ureteric stents; however, they have traditionally required two skilled operators and were associated with some stent malposition especially for proximal ureteric obstruction. We sought to investigate the efficacy and safety of a modified technique for ultrasound-assisted bedside ureteric stent insertion without the presence of a skilled assist.MethodsA single institution prospective study was performed from April-August 2023. Indications for stenting included infection, renal insufficiency, or intractable colic. Exclusion criteria included age <18 years, hemodynamic instability, and patients with history of chronic pain. Point-of-care ultrasound (POCUS) was used to confirm wire placement in the kidney and presence of a hydronephrotic drip from a 5 French ureteric catheter was used to confirm placement beyond the level of obstruction.ResultsOf 28 patients, all patients underwent successful bedside ureteric stent placement. Mean age was 64.9 years and mean body mass index (BMI) was 33.2. Proximal ureter obstruction was present in 52% of patients and mid/distal obstruction in 48%. In cases with obstructing stones, the mean stone size was 8.1 mm with a range of 4-15 mm. Infection was the indication for stent placement in most patients (71%), followed by pain (4%) and acute kidney injury (AKI) (4%). All patients who underwent successful stent placement had presence of hydronephrotic drip from the ureteric catheter.ConclusionsUltrasound-assisted bedside ureteric stent insertion without a skilled assist is a safe and feasible option for management of acute ureteral obstruction. Presence of hydronephrotic drip can indicate successful access beyond the level of obstruction as an alternative to POCUS.