The TTRACK overall diagnostic score outperformed the Mayo score in identifying ATTR-CM risk among older patients with unexplained hypertrophic cardiomyopathy (AUC 0.88 vs 0.78; P=0.0002).
Cohort (n=665)
Do the TTRACK diagnostic scores accurately identify elevated risk of ATTR-CM in older patients with unexplained hypertrophic cardiomyopathy compared to the Mayo score?
The newly developed TTRACK diagnostic scores effectively identify older patients with unexplained hypertrophic cardiomyopathy who are at high risk for ATTR-CM, outperforming the Mayo score.
Effect estimate: AUC 0.88 (95% CI 0.81-0.95)
Absolute Event Rate: 0.88% vs 0.78%
p-value: p=0.0002
Abstract Background Using data from older patients with unexplained hypertrophic cardiomyopathy (HCM) who participated in the TTRACK study, we created new transthyretin amyloid cardiomyopathy (ATTR-CM) diagnostic scores to help identify patients at high disease risk who may benefit from further screening. Purpose Describe the development/validation and potential usefulness of these new diagnostic scores in predicting increased ATTR-CM risk in the TTRACK study population. Methods TTRACK study participants were age ≥50 years and had HCM (left ventricular LV maximum wall thickness ≥15 mm on echocardiogram echo) of unknown aetiology and technetium-99m-DPD/-PYP/-HMDP–labelled bone scintigraphy scans. Patients with no cardiac uptake (grade 0 Perugini) on scans and patients with moderate/high uptake (grades 2 and 3) and no monoclonal protein abnormalities (ATTR-CM) were assigned to derivation and validation cohorts. Candidate predictive variables were analysed by univariate logistic regression, with significant variables (P0.05) entered in a multivariable logistic model. In the derivation cohort, variables independently associated with ATTR-CM were identified using sequential backward elimination; weighted risk prediction scores were built using variable beta estimates in the final model. In the validation cohort, area under the receiver-operating characteristic (AUC ROC) curves were created and optimal high-risk score cutoffs identified based on sensitivity/specificity. Final scores were assessed in the validation cohort. Results Two diagnostic scores were developed in the derivation cohort (grade 0, n=348; ATTR-CM, n=97) and tested in the validation cohort (grade 0, n=173; ATTR-CM, n=47): (1) a 6-variable/6.5-point overall score comprised of age 72 years, male sex, carpal tunnel syndrome (CTS), LV maximum posterior wall thickness 12 mm (echo), relative wall thickness 0.7 (echo), and LV ejection fraction 60%; and (2) a 3-variable/4-point simplified score comprised of age 72 years, male sex, and CTS (Fig. 1). Mean (SD) overall and simple scores were ≥2 times higher in patients with ATTR-CM than in those with no cardiac uptake (Fig. 1). When cutoffs of ≥3 and ≥2 were applied with the overall and simple scores, respectively, 81% and 49% of patients with ATTR-CM were identified as high risk for the disease vs 12% and 4% of patients with no cardiac uptake (Fig. 2). The TTRACK overall high-risk score performed better in identifying patients at risk for ATTR-CM than the Mayo score (AUC, 0.88 95% CI, 0.81, 0.95 vs 0.78 0.70, 0.87, respectively; P=0.0002); the TTRACK simple high-risk score was not significantly different than the Mayo score (0.87 0.81, 0.92 vs (0.78 0.70, 0.87; P=0.6391). Conclusion The newly developed TTRACK diagnostic scores, including a simple score with only 3 clinical variables, performed well in identifying ATTR-CM risk in older patients with unexplained HCM, warranting additional investigation.
Cappelli et al. (Sat,) conducted a cohort in Unexplained hypertrophic cardiomyopathy (n=665). TTRACK diagnostic scores vs. Mayo score was evaluated on Identification of patients at risk for ATTR-CM (AUC ROC) (AUC 0.88, 95% CI 0.81-0.95, p=0.0002). The TTRACK overall diagnostic score outperformed the Mayo score in identifying ATTR-CM risk among older patients with unexplained hypertrophic cardiomyopathy (AUC 0.88 vs 0.78; P=0.0002).