Clinical Safety and Efficacy of New-Generation Single-Layer Polytetrafluorethylene Covered Coronary Stents.

BACKGROUND: Early-generation "sandwich-design" polytetrafluorethylene (PTFE) covered coronary stents (CS) are associated with a high frequency of adverse events. New-generation single layer PTFE-CS offers the potential to enhanced procedural efficacy and improves clinical safety. Data from a dedicated study, concerning outcomes after treatment with single-layer PTFE-CS in patients undergoing percutaneous coronary intervention are scant. METHODS: This is a retrospective multicenter registry including 30 patients undergoing implantation of 39 single-layer PTFE-CS (BeGraft-coronary Stent Graft System, Bentley InnoMed GmbH, Hechingen, Germany) in native coronary arteries or saphenous bypass grafts, in 3 centers in Europe, between May 2013 and May 2019. Endpoints of interest were procedural success (placement of covered stent), binary-angiographic restenosis (BAR), percent diameter stenosis (% DS) and late-lumen loss at 6-8 months follow-up angiography, rates of target lesion revascularization (TLR), myocardial infarction (MI), stent thrombosis (ST) and mortality at 12 months. RESULTS: 28 patients underwent implantation of 37 CS due to coronary artery perforation 2 patients due to coronary artery aneurysm. Technical success was achieved in all patients (100 %). More than one stent was implanted in 7 patients (25 %) all in the perforation group. Follow-up angiography was available in 23 patients (77 %) showing favorable results: BAR = 21.8 %, %DS = 30.3 ± 27.5; LLL = 0.16 ± 0.81 mm. At 12 months all patients were alive, rates of TLR were low (3 patients, 10.0 %), there was one case of late stent thrombosis (3.3 %) and one MI (3.3 %). CONCLUSIONS: In this dedicated study, implantation of a new single layer PTFE-CS for the treatment of native coronary arteries or saphenous vein grafts after perforation or due to aneurysm showed high technical success rates and favorable angiographic and clinical efficacy. Clinical safety outcomes are encouraging, but larger prospective studies are needed to determine long-term safety of this device.

The impact of downstream coronary stenosis on fractional flow reserve assessment of intermediate left main coronary artery disease: human validation.

OBJECTIVES: The aim of this study was to determine the impact of downstream coronary stenosis in the left anterior descending coronary artery (LAD) or left circumflex coronary artery (LCx) on the assessment of fractional flow reserve (FFR) across an intermediate left main coronary artery (LMCA) stenosis in humans with the pressure wire positioned in the nondiseased downstream vessel. BACKGROUND: Accurate assessment of intermediate LMCA disease is critical for guiding decisions regarding revascularization. In theory, FFR across an intermediate LMCA stenosis will be affected by downstream disease, even if the pressure wire is positioned in the nondiseased downstream vessel. METHODS: After percutaneous coronary intervention of the LAD, LCx, or both, an intermediate LMCA stenosis was created with a deflated balloon catheter. FFR was measured in the LAD and LCx coronary arteries before and after creation of downstream stenosis by inflating an angioplasty balloon within the newly placed stent. The true FFR (FFRtrue) of the LMCA, measured in the nondiseased downstream vessel in the absence of stenosis in the other vessel, was compared with the apparent FFR (FFRapp) measured in the presence of stenosis. RESULTS: In 25 patients, 91 pairs of measurements were made, 71 with LAD stenosis and 20 with LCx stenosis. FFRtrue of the LMCA was significantly lower than FFRapp (0.81 ± 0.08 vs. 0.83 ± 0.08, p < 0.001), although the numerical difference was small. This difference correlated with the severity of the downstream disease (r = 0.35, p < 0.001). In all cases in which FFRapp was >0.85, FFRtrue was >0.80. CONCLUSIONS: In most cases, downstream disease does not have a clinically significant impact on the assessment of FFR across an intermediate LMCA stenosis with the pressure wire positioned in the nondiseased vessel.

Single bolus intravenous regadenoson injection versus central venous infusion of adenosine for maximum coronary hyperaemia in fractional flow reserve measurement.

AIMS: The aim of this study was to compare the hyperaemic effect of a single bolus regadenoson injection to a central venous adenosine infusion for inducing hyperaemia in the measurement of fractional flow reserve (FFR). METHODS AND RESULTS: One hundred patients scheduled for FFR measurement were enrolled. FFR was first measured by IV adenosine (140 µg/kg/min), thereafter by IV bolus regadenoson injection (400 µg), followed by another measurement by IV adenosine and bolus injection of regadenoson. The regadenoson injections were randomised to central or peripheral intravenous. Hyperaemic response and duration of steady state maximum hyperaemia were studied, central versus peripheral venous regadenoson injections were compared, and safety and reproducibility of repeated injections were investigated. Mean age was 66±8 years, 75% of the patients were male. The target stenosis was located in the LM, LAD, LCX, and RCA in 7%, 54%, 20% and 19%, respectively. There was no difference in FFR measured by adenosine or by regadenoson (ΔFFR=0.00±0.01, r=0.994, p<0.001). Duration of maximum hyperaemia after regadenoson was variable (10-600 s). No serious side effects of either drug were observed. CONCLUSIONS: Maximum coronary hyperaemia can be achieved easily, rapidly, and safely by one single intravenous bolus of regadenoson administered either centrally or peripherally. Repeated regadenoson injections are safe. The hyperaemic plateau is variable. Clinical Trial Registration: http://clinicaltrials.gov/ct2/ show/study/NCT01809743?term=NCT01809743&rank=1 (ClinicalTrials.gov Identifier: NCT01809743).

Depth of valve implantation, conduction disturbances and pacemaker implantation with CoreValve and CoreValve Accutrak system for Transcatheter Aortic Valve Implantation, a multi-center study.

BACKGROUND: Transcatheter Aortic Valve Implantation (TAVI) is now considered an indispensable treatment strategy in high operative risk patients with severe, symptomatic aortic stenosis. However, conduction disturbances and the need for Permanent Pacemaker (PPM) implantation after TAVI with the CoreValve prosthesis still remain frequent. METHODS AND RESULTS: We aimed to evaluate the implantation depth, the incidence and predictors of new conduction disturbances, and the need for PPM implantation within the first month after TAVI, using the new Accutrak CoreValve delivery system (ACV), compared to the previous generation CoreValve (non-ACV). In 5 experienced TAVI-centers, a total of 120 consecutive non-ACV and 112 consecutive ACV patients were included (n=232). The mean depth of valve implantation (DVI) was 8.4±4.0 mm in the non-ACV group and 7.1±4.0 mm in the ACV group (p=0.034). The combined incidence of new PPM implantation and new LBBB was 71.2% in the non-ACV group compared to 50.5% in the ACV group (p=0.014). DVI (p=0.002), first degree AV block (p=0.018) and RBBB (p<0.001) were independent predictors of PPM implantation. DVI (p<0.001) and pre-existing first degree AV-block (p=0.021) were identified as significant predictors of new LBBB. CONCLUSION: DVI is an independent predictor of TAVI-related conduction disturbances and can be reduced by using the newer CoreValve Accutrak delivery system, resulting in a significantly lower incidence of new LBBB and new PPM implantation.

Coronary spasm after the topical use of cocaine in nasal surgery.

BACKGROUND: Cocaine is a frequently used recreational drug which imposes important health problems with even life-threatening cardiotoxicity. The therapeutic use of cocaine is nowadays restricted to topical anesthesia in ophthalmological and nasal surgery but the possible hazards of this local anesthesia are not always fully appreciated. CASE REPORT: A 51-year old male patient with moderate cardiovascular risk profile underwent elective nasal surgery and cocaine was used as a local anesthetic. During surgery, ventricular arrhythmias and cardiogenic shock occurred, mimicking an ST-segment elevation myocardial infarction (STEMI) in sinus rhythm. Coronary angiography showed diffuse spasm of the right coronary artery (RCA) which disappeared with intracoronary nitrates. Urine analysis was positive for cocaine. The patient recovered completely with a normal echocardiography and ECG at discharge. CONCLUSIONS: Cocaine cardiotoxicity is not uncommon in the community but a particular situation arises when used in medicine as a topical anesthetic. This is the first case report, to our knowledge, of a cardiogenic shock mimicking a STEMI with documentation of diffuse coronary spasm after cocaine use in nasal surgery. One must be aware of the potential life-threatening complications in this low-risk surgery, moreover when safer alternatives are available.

Transesophageal echocardiography for cardiac thromboembolic risk assessment in patients with severe, symptomatic aortic valve stenosis referred for potential transcatheter aortic valve implantation.

Stroke is a devastating complication after transcatheter aortic valve implantation (TAVI) and might partially be related to cardiac embolization. The aim of this single-center prospective study was to determine the incidence of intracardiac thrombi and left atrial spontaneous echo contrast (SEC), both known predictors of cardiac embolic stroke, in patients referred for potential TAVI. One hundred four consecutive patients with severe symptomatic aortic valve stenosis and at high or very high risk for surgery were included and underwent transesophageal echocardiography. In 11 patients (10.6%), intracardiac thrombi were detected, and 25 patients (24%) showed dense grade 2 SEC. Atrial fibrillation (p <0.0001), diastolic dysfunction (p = 0.0005), and atrial size (p = 0.0038) were related to the presence of intracardiac thrombus and/or dense SEC on multivariate analysis. In conclusion, the incidence of intracardiac thrombi and dense SEC in (very) high-risk patients with severe aortic valve stenosis referred for potential TAVI is high and can accurately be detected using transesophageal echocardiography. Systematic thromboembolic evaluation using transesophageal echocardiography is thus recommended in patients referred for TAVI.

Intercostal artery pseudoaneurysm: a rare complication of transaortic transcatheter aortic valve implantation.

In this case report, we present an 86-year old patient with an intercostal pseudoaneurysm after transaortic transcatheter aortic valve implantation (TAVI). This new technique of a transaortic approach is considered a possible alternative to the more usual transfemoral, trans-subclavian or transapical access site, mainly in patients with extensive peripheral arterial disease. A mini-thoracotomy or mini-sternotomy is needed to access the ascending aorta. The patient presented with a painless but progressive pulsatile mass right parasternally, 3 months after the procedure. An intercostal pseudoaneurysm was diagnosed with duplex examination and chest CT. Successful treatment with an ultrasound-guided injection of thrombin resulted in a complete obliteration of the pseudoaneurysm. Only nine reported cases of intercostal pseudoaneurysms have been reported worldwide, and this is the first case in a patient who underwent a transaortic TAVI. Since the transaortic access is used more frequently, it is important to report on possible complications of this new technique.

Acalculous cholecystitis and tamponade: an unusual combination?

Although pericardial effusion is a well-known feature of Churg-Strauss syndrome, cardiac tamponade has rarely been encountered. The present report describes a case of Churg-Strauss syndrome that presented as an acute cholecystitis and was complicated by tamponade. Histopathological exam of both pericardium and gall bladder was conclusive for Churg-Strauss syndrome.

Effect of Morris water maze diameter on visual-spatial learning in different mouse strains.

The Morris water maze task is a widely used tool to assess hippocampus-dependent learning and memory in rodents. Performance depends upon several factors including not only the traits of the experimental animals, but also apparatus and protocol characteristics. The present study aimed at investigating the effect of maze diameter on acquisition and probe trial performance in three commonly used strains: C57Bl/6, BALB/c, and 129/SvEvBrd mice. Three maze diameters (150, 120, and 75 cm) were used under identical protocol and testing conditions. Downscaling maze dimensions, hence reducing difficulty and stress levels, did not allow BALB/c mice, commonly known as poor learners, to acquire this visual-spatial learning task. C57Bl/6 mice performed satisfactory in all three maze settings, with superior probe trial performance in the 120-cm-diameter setting. Further downscaling of maze dimensions might even render this task too simple for this strain. If the 129S5/SvEvBrd background strain is preferred, testing of visual-spatial learning abilities should be performed in a small sized MWM pool, as this strain performed only adequately in the smallest maze setting. Attention is drawn to the importance of supplying a detailed description 129 substrain nomenclature in future studies. Generalization of observations from one strain to another and from data obtained with a specific strain and maze diameter to other maze dimensions should be dealt with very carefully. The present study emphasizes the importance of a well-substantiated choice of background strain and water maze characteristics when researchers plan to investigate visual-spatial learning and memory in a chemically/lesion-induced or targeted mutagenesis model.