Acute Breathlessness Pathway Audit

Evidence

This retrospective clinical audit examined acute breathlessness pathways at Midland Metropolitan University Hospital, Sandwell and West Birmingham NHS Trust, a district general hospital in the United Kingdom. It included 70 adults referred to cardiology through electronic patient record or multiprofessional team list referral systems between March 1 and June 30, 2025. The audit reviewed D-dimer, NT-proBNP, and hs-TnI testing, imaging, and outcomes across PE, HF, and ACS pathways. Its primary audit comparison assessed CTPA yield for suspected PE against the Royal College of Radiologists (RCR) target of at least 15%; it also assessed clinically relevant alternative diagnoses on CTPA and documentation of pretest probability. pmid:42992326

Diagnostic-yield analyses were restricted to CTPA for suspected PE and coronary angiography for suspected ACS. The investigators reported yields with Wilson 95% confidence intervals and used exploratory Fisher’s exact tests for biomarker-status comparisons; analyses used IBM SPSS Statistics for Windows, version 27.0. The design therefore describes testing, imaging, and documented outcomes among patients reaching cardiology referral, rather than all people presenting with breathlessness or all people assessed for PE, HF, or ACS. pmid:42992326

Among 54 CTPAs undertaken for suspected PE, seven were positive, for a CTPA yield of 13.0% (95% CI, 6.4-24.4). This was numerically below the RCR benchmark of at least 15%. In the same CTPA group, a clinically relevant alternative diagnosis was reported in 44.4%, against a target of at least 50%, and pretest probability was documented in 22.2%, against a target of 100%. These measures characterize performance against the audit standards, not the clinical value of CTPA for an individual patient. pmid:42992326

The CTPA findings were also described by D-dimer status. PE yield was 15.0% (6/40) in patients with an elevated D-dimer, 0% (0/4) in patients with a normal D-dimer, and 10.0% (1/10) in patients without D-dimer testing. Fisher’s exact test comparisons were reported as p = 1.000 for both comparisons. D-dimer was tested in 68.6% of the 70 cardiology-referred adults, while NT-proBNP and hs-TnI were tested in 58.6% and 81.4%, respectively. One patient received none of the three biomarker tests. pmid:42992326

For the HF-related imaging pathway, left ventricular systolic dysfunction (LVSD) on transthoracic echocardiography occurred in 40.0% (8/20) of patients with elevated NT-proBNP, compared with 23.1% (3/13) of patients with non-elevated NT-proBNP and 26.3% (5/19) of patients without NT-proBNP testing. The reported exploratory comparisons were p = 0.456 for elevated versus non-elevated NT-proBNP and p = 0.501 for elevated NT-proBNP versus no testing. These comparisons describe measured differences in this referred cohort; neither comparison met conventional statistical-significance thresholds. pmid:42992326

In the ACS pathway, 47 patients had elevated hs-TnI. Of those 47 patients, 10 (21.3%) underwent coronary angiography for suspected ACS, and percutaneous coronary intervention was performed in four of the 10 patients (40.0%). Across the patients tested for hs-TnI, 29 of 57 (50.9%) had levels above the sex-specific 99th-percentile upper reference limit. Because all patients who underwent angiography for suspected ACS had elevated hs-TnI, the audit did not make an hs-TnI comparison between elevated and non-elevated groups for that angiography outcome. pmid:42992326

Analysis — Local pathway patterns

The reported pattern is consistent with a cardiology-referred population in which acute breathlessness was evaluated through overlapping PE, HF, and ACS pathways during the same admission. The 13.0% CTPA positivity estimate, with its 95% CI of 6.4-24.4, was numerically below the RCR threshold, but the audit itself characterizes comparison with that standard as indicative rather than direct because the cohort was selected through cardiology referral. D-dimer-stratified CTPA yields were accompanied by Fisher’s exact p = 1.000 comparisons, so the observed numerical differences did not provide statistically significant evidence of differences between the reported groups. pmid:42992326

Similarly, LVSD was more frequent among patients with elevated NT-proBNP than in the non-elevated or untested groups, yet the exploratory Fisher’s exact comparisons were p = 0.456 and p = 0.501. Those results quantify an observed pattern in the imaged cohort and do not establish that NT-proBNP status caused LVSD or that a biomarker-driven pathway improves outcomes. The ACS findings likewise describe selected use of angiography among patients with elevated hs-TnI, rather than the diagnostic performance of hs-TnI. The audit’s selective imaging process is central to interpretation: measured yields apply to those who underwent the relevant test, not to every referred patient. pmid:42992326

Limitations

The audit captured only patients formally referred to cardiology with dyspnea as a primary or secondary symptom. This selection means the cohort may differ from the broader population undergoing CTPA in age, comorbidity burden, and pretest probability, limiting direct comparison with the RCR standard and wider generalization. The single-center setting and four-month audit period further bound the setting represented by the results. pmid:42992326

Patients with normal or untested biomarkers were imaged less often. This partial verification bias means the reported yields do not represent sensitivity, specificity, or predictive value. Several comparator groups were small, and the authors state that nonsignificant results may reflect limited statistical power; all comparisons were exploratory. The retrospective audit also depended on the completeness and accuracy of routine electronic documentation. pmid:42992326

Pretest probability documentation was incomplete: a Wells score was documented before CTPA in 12 of 54 cases, although the score may have been calculated without being recorded. The 90-day review of patients who did not undergo CTPA had no reference standard and was confined to Trust records, so missed diagnoses, including presentations to hospitals outside the Trust, could not be excluded. These features limit inference about diagnostic accuracy, missed events, and pathway effectiveness. pmid:42992326