Prediction of obstructive coronary artery disease and prognosis in patients with suspected stable angina.

AIMS: We hypothesized that the modified Diamond-Forrester (D-F) prediction model overestimates probability of coronary artery disease (CAD). The aim of this study was to update the prediction model based on pre-test information and assess the model's performance in predicting prognosis in an unselected, contemporary population suspected of angina. METHODS AND RESULTS: We included 3903 consecutive patients free of CAD and heart failure and suspected of angina, who were referred to a single centre for assessment in 2012-15. Obstructive CAD was defined from invasive angiography as lesion requiring revascularization, >70% stenosis or fractional flow reserve <0.8. Patients were followed (mean follow-up 33 months) for myocardial infarction, unstable angina, heart failure, stroke, and death. The updated D-F prediction model overestimated probability considerably: mean pre-test probability was 31.4%, while only 274 (7%) were diagnosed with obstructive CAD. A basic prediction model with age, gender, and symptoms demonstrated good discrimination with C-statistics of 0.86 (95% CI 0.84-0.88), while a clinical prediction model adding diabetes, family history, and dyslipidaemia slightly improved the C-statistic to 0.88 (0.86-0.90) (P for difference between models <0.0001). Quartiles of probability of CAD from the clinical prediction model provided good diagnostic and prognostic stratification: in the lowest quartiles there were no cases of obstructive CAD and cumulative risk of the composite endpoint was less than 3% at 2 years. CONCLUSION: The pre-test probability model recommended in current ESC guidelines substantially overestimates likelihood of CAD when applied to a contemporary, unselected, all-comer population. We provide an updated prediction model that identifies subgroups with low likelihood of obstructive CAD and good prognosis in which non-invasive testing may safely be deferred.

Interfering antibodies may contribute to elevated D-dimer: a case report.

BACKGROUND: Plasma levels of D-dimer are elevated in patients with thromboembolisms. Here we investigated the existence of interfering antibodies as a potential cause for elevated D-dimer levels. CASE PRESENTATION: A 42-year-old white Caucasian woman with a prior history of pulmonary embolism during her first pregnancy (treated with heparin therapy for 6 weeks postnatally) and hypothyroidism had a persistent elevated D-dimer without any clinical or ultrasound-based signs of thromboembolic conditions during her second pregnancy. We obtained informed consent and plasma was obtained from the patient. D-dimer levels were measured using two different assays. We also tested for the presence of rheumatoid factor, performed dilution series, and finally used an antibody depletion strategy. The two D-dimer assays performed similarly. Using our antibody depletion technique, we observed that ~ 1/3 of the increased plasma levels of D-dimer may be attributed to interfering antibodies. CONCLUSIONS: Our results identify interfering antibodies as a potential contributor to an increased D-dimer in this patient. Our case highlights the potential of heterophilic interference for increased D-dimer and provides a procedure to determine this analytically.

[Perioperative heparin bridging is rarely indicated].

Numerous studies have shown that perioperative heparin bridging in patients treated with a vitamin K antagonist leads to an increased incidence of bleeding and so far, there is no evidence that it leads to a significant reduction in postoperative thromboembolism as summarised in this review. Prophylactic dosage of heparin is recommended after major surgery. Heparin bridging is not relevant in patients receiving a direct oral anticoagulant due to the rapid onset and offset of action of DOACs.

Low diagnostic yield of non-invasive testing in patients with suspected coronary artery disease: results from a large unselected hospital-based sample.

Aims: Stable angina is the most common presentation of heart disease and has a good prognosis. With declining coronary artery disease (CAD), rates a diagnostic approach balancing costs and benefits is a challenge, particularly in women. This study describes the real-life diagnostic workup in a large hospital to explore whether the diagnostic approach may be improved. Methods and results: We identified 4028 patients free of CAD, referred for and assessed with non-invasive (NIT) or invasive test for stable suspected CAD in 2012-15. In both the sexes, the majority (>85%) presented with chest pain as primary symptom. Women had more non-angina (60.2 vs. 54.5%) and less typical angina (8.2 vs. 11.8%, P < 0.001). Despite a mean pretest probability of 20.9% in women and 45.1% in men (P < 0.001), only 69 (3.1%) women and 190 men (10.4%) were diagnosed with obstructive CAD. In all, 93% underwent a NIT and 80% of these were normal. Among the 1238 men and 1595 women with non-angina or dyspnoea, only 6.1% and 2.9%, respectively, had positive NIT. After multiple adjustments, women remained less likely to have positive NIT [odds ratio (OR) 0.42 95% confidence interval (95% CI 0.32-0.56)] and given a positive test also less likely to have obstructive CAD [OR 0.30 (0.17-0.52)]. The C-statistics for predicting positive NIT was 0.77 (0.72-0.82) in women and 0.77 (0.74-0.80) in men. Conclusion: These data confirm the very low diagnostic yield of non-invasive and invasive assessment of CAD in current clinical practice, particularly in women and in patients with atypical symptoms. Data call for a more rational approach to avoid unnecessary testing.