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.