Current practice of Dutch cardiologists in detecting and diagnosing atrial fibrillation: results of an online case vignette study.

INTRODUCTION: Detection of atrial fibrillation (AF) is important given the risk of complications, such as stroke and heart failure, and the need for preventive measures. Detection is complicated because AF can be silent or paroxysmal. Describing current practice may give clues to improve AF detection. The aim of this study was to describe how cardiologists currently detect AF. METHODS: Between December 2014 and May 2015, we sent Dutch cardiologists an online questionnaire. Firstly, we asked which tools for detection of AF their department has. Secondly, we presented six case vignettes related to AF, in which they could choose a diagnostic tool. Thirdly, we compared the results with current guidelines. RESULTS: We approached 90 cardiology departments and 48 (53%) completed the questionnaire. In asymptomatic patients with risk factors according to CHA2DS2-VASc, 40% of the cardiologists would screen for AF. In patients with signs or symptoms of AF, all but one cardiologist would start a diagnostic process. In both vignettes describing patients with non-frequent symptoms, 46% and 54% of the responders would use short-term (i. e. 24- or 48-hour) electrocardiographic monitoring, 48% and 27% would use long-term (i. e. 7 day, 14 day or one month) monitoring. In both cases describing patients with frequent symptoms, 85% of the responders would use short-term and 15% and 4% long-term monitoring. CONCLUSION: Dutch cardiologists have access to a wide variety of ambulatory arrhythmia monitoring tools. Nearly half of the cardiologists would perform opportunistic screening. In cases with non-frequent symptoms, monitoring duration was shorter than recommended by NICE.

Accuracy of X-ray with perfusion scan in young patients with suspected pulmonary embolism.

BACKGROUND: Computed tomography pulmonary angiogram (CTPA) has become the standard test in the diagnostic workup of patients with suspected pulmonary embolism (PE). However, young patients may have an increased risk of cancer with CTPA. Perfusion scanning combined with chest X-ray (X/Q) may offer an adequate alternative, but has never been prospectively validated. We directly compared this strategy with CTPA in patients aged ≤50years with suspected PE. METHODS: Consecutive patients with a likely clinical probability or an abnormal D-dimer level underwent both CTPA and X/Q. Two trained and experienced nuclear physicians independently analyzed the X/Q-scans. The accuracy of X/Q according to the PISAPED criteria was calculated in terms of sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). RESULTS: Seventy-six patients were included, with a PE rate of 33%. The inter-observer agreement for X/Q-scan reading was high (κ=0.89). After consensus reading, 21 patients (28%) were categorized as 'PE present', 53 (70%) as 'PE absent', and two (2.6%) as 'non-diagnostic'. In 22%, there was a discrepancy between the X/Q-scan and CPTA for the diagnosis or exclusion of PE. The PPV and NPV were 71% and 83%, respectively. CONCLUSION: In patients with a high risk of PE, a diagnostic strategy of chest X-ray and perfusion scanning using the PISAPED criteria seems less safe than CTPA. Additional studies should further investigate this diagnostic algorithm.

Qualitative point-of-care D-dimer testing compared with quantitative D-dimer testing in excluding pulmonary embolism in primary care.

BACKGROUND: General practitioners can safely exclude pulmonary embolism (PE) by using the Wells PE rule combined with D-dimer testing. OBJECTIVE: To compare the accuracy of a strategy using the Wells rule combined with either a qualitative point-of-care (POC) D-dimer test performed in primary care or a quantitative laboratory-based D-dimer test. METHODS: We used data from a prospective cohort study including 598 adults suspected of PE in primary care in the Netherlands. General practitioners scored the Wells rule and carried out a qualitative POC test. All patients were referred to hospital for reference testing. We obtained quantitative D-dimer test results as performed in hospital laboratories. The primary outcome was the prevalence of venous thromboembolism in low-risk patients. RESULTS: Prevalence of PE was 12.2%. POC D-dimer test results were available in 582 patients (97%). Quantitative test results were available in 401 patients (67%). We imputed results in 197 patients. The quantitative test and POC test missed one (0.4%) and four patients (1.5%), respectively, with a negative strategy (Wells ≤ 4 points and D-dimer test negative) (P = 0.20). The POC test could exclude 23 more patients (4%) (P = 0.05). The sensitivity and specificity of the Wells rule combined with a POC test were 94.5% and 51.0% and, combined with a quantitative test, 98.6% and 47.2%, respectively. CONCLUSIONS: Combined with the Wells PE rule, both tests are safe to use in excluding PE. The quantitative test seemed to be safer than the POC test, albeit not statistically significant. The specificity of the POC test was higher, resulting in more patients in whom PE could be excluded.

Variable D-dimer thresholds for diagnosis of clinically suspected acute pulmonary embolism.

BACKGROUND: Computed tomography pulmonary angiography (CTPA) is frequently requested using diagnostic algorithms for suspected pulmonary embolism (PE). For suspected deep vein thrombosis, it was recently shown that doubling the D-dimer threshold in patients with low pretest probability safely decreased the number of ultrasonograms. We evaluated the safety and efficiency of a similar strategy in patients with suspected PE. METHODS: We performed a post-hoc analysis of 2213 consecutive patients of two cohort studies with suspected PE who were managed according to current standards: PE ruled out in case of unlikely probability (Wells rule ≤ 4 points) and a D-dimer level < 0.5 µg mL(-1) . CTPA was performed in all other cases. All patients were followed for 3 months. We calculated 3-month venous thromboembolism (VTE) incidence and the number of required CTPAs for selective D-dimer thresholds in patients with low clinical probability (< 2 points, D-dimer threshold < 1.0 µg mL(-1) ) and intermediate probability (2-6 points, D-dimer threshold < 0.5 µg mL(-1) ). RESULTS: Using standard management, PE could be excluded without CTPA in 26% of patients, with a 3-month VTE incidence of 0.88% (95% confidence interval [CI] 0.29-2.1%). Using selective D-dimer thresholds, PE could be excluded without CTPA in 36% of patients, with a 3-month VTE incidence of 2.1% (95% CI 1.2-3.4%) in patients managed without CTPA, an increase of 1.2 percentage points (95% CI -0.3 to 2.2). CONCLUSIONS: Applying selective D-dimer thresholds reduces the need for CTPA by 11 percentage points but is associated with an increased failure rate. Prospective studies should evaluate the safety and net clinical benefit of this approach.

Safety of outpatient treatment in acute pulmonary embolism.

INTRODUCTION: Data regarding outpatient treatment of pulmonary embolism (PE) is scarce. This study evaluates the safety of outpatient management of acute PE. METHODS: This is a retrospective cohort study of consecutive patients presenting at the Ottawa Hospital with acute PE diagnosed between 1 January 2007 and 31 December 2008. PE was defined as an arterial filling defect on CTPA or a high probability V/Q scan. Patients were managed as outpatients if they were hemodynamically stable, did not require supplemental oxygenation and did not have contraindications to low-molecular-weight heparin therapy. RESULTS: In this cohort of 473 patients with acute PE, 260 (55.0%) were treated as outpatients and 213 (45.0%) were admitted to the hospital. The majority of the patients were admitted because of severe comorbidities (45.5%) or hypoxia (22.1%). No outpatient died of fatal PE during the 3-month follow-up period. At the end of follow-up, the overall mortality was 5.0% (95% CI, 2.7-8.4%). The rates of recurrent venous thromboembolism (VTE) in outpatients were 0.4% (95% CI, 0.0-2.1%) and 3.8% (95% CI, 1.9-7.0%) within 14 days and 3 months, respectively. The rates of major bleeding episodes were 0% (95% CI, 0-1.4%) and 1.5% (95% CI, 0.4-3.9%) within 14 days and 3 months, respectively. Four (1.5%) outpatients were admitted to the hospital within 14 days. CONCLUSIONS: A majority of patients with acute PE can be managed as outpatients with a low risk of mortality, recurrent VTE and major bleeding episodes.