Systematic hand-held echocardiography in patients hospitalized with acute coronary syndrome.

AIMS: Transthoracic echocardiography is recommended in all patients with acute coronary syndrome but is time-consuming and lacks an evidence base. We aimed to assess the feasibility, diagnostic accuracy, and time efficiency of hand-held echocardiography in patients with acute coronary syndrome and describe the impact of echocardiography on clinical management in this setting. METHODS AND RESULTS: Patients with acute coronary syndrome underwent both hand-held and transthoracic echocardiographies with agreement between key imaging parameters assessed using kappa statistics. The immediate clinical impact of hand-held echocardiography in this population was systematically evaluated. Overall, 262 patients (65 ± 12 years, 71% male) participated. Agreement between hand-held and transthoracic echocardiographies was good-to-excellent (kappa 0.60-1.00) with hand-held echocardiography having an overall negative predictive value of 95%. Hand-held echocardiography was performed rapidly (7.7 ± 1.6 min) and completed a median of 5 (interquartile range 3-20) h earlier than transthoracic echocardiography. Systematic hand-held echocardiography in all patients with acute coronary syndrome identified an important cardiac abnormality in 50%, and the clinical management plan was changed by echocardiography in 42%. In 85% of cases, hand-held echocardiography was sufficient for patient decision-making, and transthoracic echocardiography was no longer deemed necessary. CONCLUSION: In patients with acute coronary syndrome, hand-held echocardiography provides comparable results to transthoracic echocardiography, can be more rapidly applied, and gives sufficient imaging information for decision-making in the vast majority of patients. Systematic echocardiography has clinical impact in half of patients, supporting the clinical utility of echocardiography in this population and providing an evidence base for current guidelines.

Validation of a Novel System for Co-Registration of Coronary Angiographic and Intravascular Ultrasound Imaging.

INTRODUCTION: Intravascular ultrasound (IVUS) is a useful adjunct to guide percutaneous coronary intervention (PCI). Correlating IVUS images with angiographic findings can be challenging. We evaluated the utility of a novel co-registration system for IVUS and coronary angiography. METHODS AND RESULTS: A 3-D virtual catheter trajectory was constructed from separate angiographic imaging runs using bespoke software. Intravascular ultrasound images were obtained using a commercially available mechanical rotational transducer with motorized pullback. Co-registration of ultrasound and angiographic images was then performed retrospectively based on the length of pullback, the 3-D trajectory and the start position of the catheter. Validation was performed in a spherical phantom model and in vivo in the coronary circulation of patients undergoing coronary angiography and intravascular imaging for clinical purposes. 111 paired angiographic and IVUS runs were performed in 3 phantom models. The differences between the reference length and the length measured on the 3D reconstructed path was -0.01 ±â€¯0.40 mm. Intra-observer variability was 0.4%. We enrolled 25 patients in 3 European hospitals and performed 35 co-registration attempts with an 86% success rate. 71 landmarks were selected by the first operator, 68 by the second. Differences between angiographic and IVUS landmarks were -0.22 ±â€¯0.72 mm and 0.05 ±â€¯1.01 mm, respectively. Inter-observer variability was 0.23 ±â€¯0.63 mm. CONCLUSION: We present a novel method for the co-registration of IVUS and coronary angiographic images. This system performed well in a phantom model and using images obtained from the human coronary circulation. CLASSIFICATIONS: Innovation, intravascular ultrasound, other technique.

Patent haemostasis prevents radial artery occlusion in patients with an acute coronary syndrome.

BACKGROUND: A haemostatic technique that maintains radial artery flow ("patent haemostasis") following transradial catheterization reduces rates of radial artery occlusion (RAO) in patients with stable coronary disease. It is unclear whether this benefit extends to patients with an acute coronary syndrome (ACS). METHODS: Patients undergoing inpatient transradial catheterization for an ACS were prospectively enrolled in a consecutive cohort study (n=300). Radial haemostasis was obtained using standard radial compression (cohort 1; n=150) or patent haemostasis (cohort 2; n=150). An end-of-case activated clotting time (ACT) was recorded and radial artery patency assessed within 24 hours of sheath removal by reverse Barbeau's test. RESULTS: The incidence of RAO was 16.0% following standard radial compression and 5.3% following patent haemostasis (p=0.003). Univariate predictors of RAO were patent haemostasis (OR 0.30; [0.13-0.68], p=0.004), hyperlipidaemia (OR 0.46; [0.21-0.98], p=0.04), history of current smoking (OR 2.86; [1.3-6.0], p=0.015) and longer procedure times (OR 1.03/additional minute; [1.01-1.05], p=0.003). There was no association between the end-of-case ACT and RAO (OR 1.00; [0.9-1.01] p=1.00). After adjusting for covariates, patent haemostasis reduced the risk of RAO by 70% compared to standard compression (OR 0.30; [0.12-0.77], p=0.12). The c-statistic for model discrimination was 0.79 (95% CI [0.71-0.86], p<0.001). Inverse probability treatment weighted analysis also confirmed patent haemostasis as an independent predictor of reduced RAO (OR 0.38 [0.15-0.95], p=0.039). CONCLUSION: Patent haemostasis is highly effective in preventing early RAO in patients with ACS.