Diagnostic accuracy and reclassification potential of the acoustic CADScor algorithm in intermediate risk patients with suspected coronary artery disease

Background

Validation studies of the 2019 European Society of Cardiology pre-test probability model (ESC-PTP) for coronary artery disease (CAD) report that 35–40% of patients have intermediate pre-test risk (ESC-PTP 5-<15%). A clear strategy for deferral or referral in this group has not been established. Stratification tools with a high negative predictive value (NPV) are especially wanted to improve pre-test risk estimates.

Acoustic detections of coronary stenosis are a new technology which could potentially be useful to supplement PTP stratification. One of the devices, the CADScor®System, has been shown to down-classify >40% of patients to low risk without increasing CAD prevalence. However, the clinical utility of using the CADScor algorithm (version (V)3.1) has not be validated.

Purpose

1) To validate the diagnostic performance of the CADScor®System (V3.1), and 2) to study the reclassification potential of a clinical likelihood strategy by ESC-PTP estimation supplemented by a CAD-score.

Methods

In total, 1732 patients without known CAD but with symptoms suggestive hereof underwent coronary CTA as a first-line diagnostic test. Based on an interview prior to coronary CTA, the ESC-PTP model was applied and sound recordings were performed using the acoustic CADScor® System. Patients with a suspected >50% diameter stenosis in any coronary segment at coronary CTA were referred to investigation with Invasive angiography (ICA) with measurement of Fractional flow reserve (FFR).

The ESC-PTP risk estimation was divided according to the recommended cut-offs of <5%, 5-<15% and >15% PTP of obstructive CAD. Haemodynamically obstructive CAD was defined as: (1) FFR value <0.80, (2) luminal diameter stenosis reduction >90%, or (3) luminal diameter stenosis reduction ≥50% if FFR was indicated but not performed. A predefined cut-off value of 20 was used for CAD-score values to rule-out CAD.

Results

A suspected stenosis was found in 439 patients (26%) after coronary CTA. The follow up with ICA with FFR showed significant stenoses in 198 patients (12%).

In the entire cohort using the ≤20 CAD-score cutoff for CAD rule-out, sensitivity was 85.3% (95% CI 79.5–89.9%), specificity was 40.3% (95% CI 37.8–42.9%), the PPV was 5.9% (95% CI 13.8–18.3%)), and the NPV was 95.4% (95% CI 93.4–96.9%). Hence, the disease prevalence of obstructive CAD was 4.6% in the ruled-out patients.

Applying the ≤20 CAD-score cutoff for CAD rule-out in intermediate risk patients (ESC-PTP 5-<15%) a total of 316 patients (48%) were down-classified to low risk with an obstructive CAD prevalence of 3.5%.

Conclusion

Having high NPV, the CADscor holds excellent rule-out power. Interestingly, the CADscor has reclassification properties in intermediate CAD risk patients where almost 50% can be deferred form further testing without increasing obstructive CAD risk. Thus, the CADscor can supplement clinical assessment to guide decisions on the need for further testing.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): The study was supported by the Health Research Fund of Central Denmark Region, Aarhus University Research foundation and by an institutional research grant from Acarix A/S, Denmark. Patient flowReclassification potential

P870A genetic risk score is associated with increased coronary plaque burden but not specific plaque features: a coronary computed tomography study

Background

Genetic risk scores (GRSs) based on risk variants identified from genome-wide association studies (GWASs) predict coronary artery disease (CAD) risk. However, it is unknown whether the GRS is associated with coronary plaque burden or specific high-risk plaque features responsible for the clinical disease onset.

Purpose

To investigate if a GRS is associated with coronary plaque burden and specific plaque characteristics, in patients with suspected stable CAD referred for coronary computed tomography angiography (CTA).

Methods

We consecutively included and genotyped 1645 patients undergoing coronary CTA. Using LDPred, a previously validated GRS was calculated as the weighted sum of the number of CAD risk variants identified from the CARDIoGRAMplusC4D GWAS meta-analysis. Plaques were evaluated using an 18-segment model and characterized by stenosis severity (0%, 1–49%, 50–69%, 70–100%) and composition (calcified (>80% calcified), mixed-calcified (50–80% calcified), mixed-soft (20–50% calcified), or soft (<20% calcified)). The segment stenosis score and the coronary artery calcium score (CACS) were used as measures of plaque burden. Multivariate regression models were used to assess the effect per standard deviation (SD) of the GRS with adjustment for age, sex, hypertension, hypercholesterolemia, BMI, chest pain symptoms, and active smoking.

Results

For each SD increase in the GRS, the segment stenosis score increased with 49% (p=8.6e-27) and CACS increased with 110% (p=2.3e-24). The GRS was associated with a higher risk of plaque stenosis >50% (OR: 1.74, p=3.2e-15), calcified (OR: 1.65, p=3.0e-16), mixed-calcified (OR: 1.64, p=1.5e-8), mixed-soft (OR: 1.44, p=1.6e-6), and soft plaques (OR: 1.40, p=3.0e-6), and all coronary vessels were more often affected with plaques (all p-values <1.0e-4).

When analyzing the plaque characteristics (3007 plaques in 849 patients), the GRS was associated with stenosis severity (OR per severity category: 1.15 (p=0.005), but not with extent of calcification, proximal location, or presence in any of the major coronary vessels (all p-values >0.05).

GRS and Plaque burden

Conclusion

The GRS was strongly associated with the extent and severity of CAD at coronary CTA, but not any specific plaque characteristics per se. The results may suggest that polygenic risk based on large CAD-GWAS increases CAD risk through increased coronary plaque burden rather than specific plaque features.

P2713A genetic risk score improves discrimination of hemodynamically obstructive coronary artery disease (CAD) beyond the CAD Consortium scores in patients at low-to-intermediate risk of CAD

Background

Genetic risk scores (GRSs), based on variants identified in genome-wide association studies (GWAS), have been shown to predict risk of coronary artery disease (CAD). However, the clinical potential remains unknown.

Purpose

To investigate whether a GRS improves discrimination of hemodynamically obstructive CAD beyond the CAD Consortium scores and coronary artery calcium score (CACS) in patients referred for coronary computed tomography angiography (CTA).

Methods

We consecutively included and genotyped 1645 patients undergoing CACS scoring and coronary CTA on a suspicion of CAD. Using LDPred, a recently validated GRS was calculated as the weighted sum of the number of CAD risk variants identified from the CARDIoGRAMplusC4D GWAS meta-analysis. Patients with a ≥50% stenosis on CTA further underwent invasive coronary angiography (ICA) with fractional flow reserve (FFR). Hemodynamically obstructive CAD was defined as a visual ICA stenosis >90%, FFR <0.80, or a quantitative coronary analysis stenosis >50% if FFR was not feasible. Discrimination was evaluated by receiver-operating characteristics.

Results

Median age was 57 (interquartile range 50–64) years and 799 (49%) were males. Hemodynamically obstructive CAD was present in 14 (4%) with a low GRS (<20th percentile), 91 (9%) with an intermediate GRS (20th–80th percentile) and 53 (16%) with a high GRS (>80th percentile) (p<0.0001). Adding the GRS improved the area under the receiver-operating curve (AUC) on top of the CAD Consortium basic score (from 0.67 to 0.72, p=0.0052), and the CAD Consortium clinical score (0.70 to 0.74, p=0.0084), but not on top of the CAD Consortium clinical score + CACS (0.85 to 0.86, p=0.30). Improvement in discrimination on top of the CAD Consortium scores was predominantly driven by females ≤57 years (CAD Consortium basic score ± GRS: 0.60 to 0.78, p=0.0004; CAD Consortium clinical score ± GRS: 0.63 to 0.78, p=0.0007). The GRS did not improve discrimination in any subgroups including CACS (CAD Consortium clinical score + CACS ± GRS: all p-values >0.05).

Conclusion

A GRS improves discrimination of hemodynamically obstructive CAD beyond CAD consortium scores, particularly in young women. However, the additive discriminative value is attenuated in models including CACS.

Disturbance in rhythm in 2 patients with a permanent pacemaker and two endocardial electrodes

Rhythm disturbances are described in 2 patients with an implanted permanent pacemaker. Both patients had nonfunctioning electrodes retained after previous complications. It was possible to observe, in both patients, during fluoroscopic examination that the electrodes occasionally touched each other. The etiology of the rhythm disturbances are discussed on the basis of the technical specifications of the pace makers. The interpretation of rhythm disturbances in patients with implanted pacemakers presents special problems. Disturbances in rhythm can be spontaneous and have no relation to, but possibly modified, by the implanted pacemaker. However, the rhythm disturbances can also result from the technical specifications of the implanted pacemaker or from defects in the same. The following case histories disturbances in rhythm in two patients, who both had 2 endocardial electrodes of which only one was connected to the implanted pacemaker.

[Surgeons' experience of complication frequency--registration validity for legal abortion]

INTRODUCTION

The aim was to investigate the degree to which experience influenced the complication rate (cr) in legal abortion. We also compared our cr with that registered by the National Health Service for the same group of patients.

MATERIAL

760 legal abortions from 1993 to 1994 were reviewed retrospectively.

RESULTS

We found an overall cr of 8.7% (95% confidence limit: 6.7-10.7). The cr was the same for all groups of doctors, from the youngest to the most senior and experienced surgeons. The experience in months of the younger surgeons was noted for each intervention, and we found that they did not improve their results over time or by practice. In the same study, we found that the National Health Service had received, registered, and published statistical data from the hospitals, which were not entirely accurate.

CONCLUSION

The complication rate was not associated with the experience of the surgeon.

[Legal abortion. An analysis of factors which can affect frequency of complications]

INTRODUCTION

Due to a rather high complication rate, we decided to analyze data from women, who were readmitted to hospital with complications to legal abortion.

MATERIAL

760 legal abortions performed in 1993-1994 were retrospectively reviewed for complications.

RESULTS

We found 66 complications (8.7% (95% confidence limits (6.7-10.7)), that resulted in readmission to hospital. The distribution of complications was as follows: retention 41 (62% (50-74)), infection 12 (18% (9-27)), bleeding and pain 11 (17% (8-26)) and perforation two (3% (0-7)). There was a slight correlation between a stronger midline echo on ultrasound measurement of the uterine cavity and finding placental tissue on histological examination of the material obtained from reevacuation. The time interval between legal abortion and reevacuation was nine days. Retroflexio uteri was not correlated with reevacuation.

CONCLUSIONS

We found a statistically increased risk of complications following legal abortion relative to the figures reported by the national health authority, but not significantly higher than that found in other reports. Moreover, a conservative attitude to retention can reduce the number of reevacuatio uteri after legal abortion.

[Intravesical drug therapy in women with severe urge incontinence. Clinical experiences from a department of gynecology]

Conventional oral pharmacotherapy for urge incontinence remains problematic because of limited efficacy and systemic side effects. In this study 27 patients with severe urge incontinence were treated with intravesical drugs (emepron 200 mg or oxybutynin 5 mg) twice a day. They had previously on average undergone 3.3 other treatment options without satisfactory effect. The average age was 62 years, and their incontinence had on average lasted for 15 years. Seven percent were cured and 41% were improved. Fifty-two percent had no satisfactory effect of the treatment. The number of side effects was low, and none left the study for this reason. Intravesical anticholinergic pharmacotherapy can be a treatment option in women with severe urge incontinence.

[Imperforate hymen. A simple, but overlooked diagnosis]

About one among 2000 girls have hymen imperforatus. Some are recognized because of mucocolpos at birth, but the diagnosis is usually not detected before puberty. Menstrual blood will accumulate behind the imperforate hymen, and result in abdominal pain, distension of the lower abdomen and often in acute urinary retention. The diagnosis and treatment is easy, but many patients have seen several doctors before the diagnosis is clear.

Prognosis after the first episode of gastrointestinal bleeding or coma in cirrhosis. Survival and prognostic factors

Hepatic encephalopathy and gastrointestinal (GI) bleeding are the most serious complications in cirrhosis. The purpose of this study was to examine survival after the first episode of GI bleeding or coma, or both, and to identify variables associated with the subsequent survival in 284 consecutive patients with cirrhosis admitted to one division of hepatology over a period of 81 months. Patients who only bled had markedly longer survival than those who only had coma, whereas those who had both bleeding and coma had by far the poorest survival, only 15% being alive 1 year later. Several other variables showed a significant association with survival. In a Cox multiple regression analysis the following four variables showed significant association with a short survival: coma and bleeding at the episode, ascites, low prothrombin index, and high serum creatinine. The prognostic index derived from the Cox model, which was validated by a split-sample testing technique, may be used to refine prognostic estimation in this subgroup of severely ill cirrhotic patients.

Regional pulmonary blood flow in mitral disease studied by xenon radiospirometry

Regional lung perfusion was measured in the sitting position by 4 external detectors after intravenous injection of 133Xe in 24 patients with mitral valve disease and in 8 people with no cardiopulmonary disease acting as normal controls. Right- and left-sided heart catheterization was carried out on the patients on the following day. Mitral valve stenosis was found in 9, mitral valve regurgitation in 8, and both stenosis and regurgitation in the remaining 7. Regional lung perfusion in the normal people fell linearly from the basal to the apical sections of the lungs. The perfusion distribution in patients with mitral valve disease and a pulmonary capillary vein (PCV) pressure lower than 15 mmHg (2-0 kPa) did not differ significantly from that of the controls. A redistribution of the regional perfusion, with an increase in the apical perfusion and a fall in the basal perfusion of the lungs, was seen in patients with a raised PCV pressure. The hyperperfusion of the apical lung sections correlated with the mean pressure in the pulmonary artery (r=+0-795, P less than 0-001), while the basal hypoperfusion correlated with the PCV pressure (r=0-842, P less than 0-001). The PCV pressure can be predicted with an exactitude of +/- 7 mmHg (0-9 kPa) (95% confidence limits). Neither the cardiac index nor the pulmonary vascular resistance correlated with the changes in perfusion. Xenon radiospirometry is a rapid and reliable method for evaluating PCV pressure before or after operation in patients with mitral valve disease.