Evidence · K243866

The whole evidence base.

Every number behind InVision Precision Cardiac Amyloid1 — the FDA validation, peer-reviewed international validation across five sites in two countries, and a heart-failure cohort at Northwestern Medicine. Including the metrics where we score lower.

FDA 510(k) K243866

Cleared 21 May 2025 as decision-support AI. Class II, product code SDJ.

60.7%
Sensitivity
99.0%
Specificity
ItemValue
Validation cohort1,221 unique echocardiogram studies
Sites3 US sites
Case-to-control ratio1:2
Reference standardConfirmatory imaging or pathology
Views usedApical four-chamber and parasternal long-axis
Intended populationAdults aged 65 and older
Clearance typeDecision-support AI (FDA device type: Adjunctive Cardiac Amyloidosis Status Indicator)
Subgroup analysesAge, gender, BMI, race/ethnicity, amyloidosis type, site, and imaging manufacturer — all met acceptance criteria
Human factors validationn=31 (16 non-cardiologists, 15 cardiologists)
Prior designationsBreakthrough Device Designation (January 2024); FDA TAP enrolment

Peer-reviewed international validation

JACC: Advances, 2025. Temporally and geographically distinct external validation, conducted by investigators at five institutions across two countries.

MetricValueConfidence interval
Overall AUC 0.893 95% CI 0.874–0.912
Sensitivity 0.648 95% CI 0.607–0.687
Specificity 0.982 95% CI 0.971–0.989
PPV in the case-control set (37% cases) 0.954 95% CI 0.928–0.972
NPV in the case-control set (37% cases) 0.826 95% CI 0.804–0.848

The cohort

Cases574 patients with cardiac amyloidosis
Controls979 matched controls, all aged 65 and older
CountriesUnited States and Japan
Case mixATTR 67.8%, AL 29.4%, other 2.8%
Reference standardBone-tracer nuclear imaging, monoclonal gammopathy testing, genetic testing, and/or tissue biopsy
Sites Cedars-Sinai Medical Center · Keio University, Tokyo · Northwestern Medicine · Kumamoto University · Yale-New Haven
We publish the worst site, not just the best. Site-level AUC ranged from 0.833 (95% CI 0.753–0.906) at Kumamoto University to 0.944 (95% CI 0.911–0.971) at Keio University. A vendor that reports only a pooled figure is hiding its floor.

How to read sensitivity and specificity

Sensitivity and specificity trade against each other. An operating point tuned to catch more cases accepts more false flags; one tuned so that nearly every flag is real misses more cases. InVision Precision Cardiac Amyloid is set for specificity: 99.0% specificity at 60.7% sensitivity.

Method — check our work

PPV = (sens × prev) ÷ [ (sens × prev) + (1 − spec) × (1 − prev) ]

NPV = (spec × (1 − prev)) ÷ [ (spec × (1 − prev)) + (1 − sens) × prev ]

Computed from the K243866 validation counts: sensitivity 247/407 (0.607), specificity 806/814 (0.990). Predictive values depend on the prevalence of the population tested, so the table shows a range rather than a single number.

PrevalencePPVNPV True flagsper 1,000 False flagsper 1,000 Missedper 1,000
1% 38.4% 99.60% 6.1 9.7 3.9
2% 55.8% 99.20% 12.1 9.6 7.9
5% 76.5% 97.95% 30.3 9.3 19.7
10% 87.3% 95.78% 60.7 8.8 39.3
14% 91.0% 93.93% 85.0 8.5 55.0

In the peer-reviewed international validation, PPV was 0.954 (95% CI 0.928–0.972) in a case-control set where 37% of studies were cases. That figure reflects the study design; it is not the PPV in a clinical population.

The honest counterpart, stated plainly: a higher-specificity operating point misses more cases. At 60.7% sensitivity, a negative result does not exclude cardiac amyloidosis.

Heart-failure cohort

JACC: Advances 2025. Northwestern-led. Integrated health system, 2010–2022. 176 confirmed ATTR-CM cases and 3,192 heart failure controls, matched to a target prevalence of 5%. Evaluated at the developer-specified threshold, ≥0.8. Every metric for our model is shown, including where it scores lower.

Metric InVision Precision
Cardiac Amyloid
F1 0.610.55–0.67
Accuracy 0.960.96–0.97
Sensitivity 0.570.50–0.64
Specificity 0.980.98–0.99
PPV 0.660.58–0.74
NPV 0.980.97–0.98
False negative rate 0.430.35–0.51
Average precision 0.620.55–0.69
AUC 0.880.84–0.91

The AUC confidence interval for InVision appears as 0.84–0.91 in Table 3 and 0.85–0.91 in the body text. Table 3 is cited here.

Subgroups

Moderate or greater left ventricular hypertrophy (n=504, prevalence 23.8%)

MetricInVision
Sensitivity 0.660.57–0.74
Specificity 0.960.94–0.98
Average precision 0.810.74–0.87
AUC 0.910.88–0.94

LVEF below 40% (n=713)

MetricInVision
Sensitivity 0.590.43–0.77
Specificity 0.980.97–0.99
Average precision 0.650.45–0.79
AUC 0.880.79–0.95
No result for some patients. The model produced no prediction for roughly 15% to 20% of patients, because of clip length, image quality, view classification, or low model confidence. The authors note real-world sensitivity may therefore be lower than the primary analysis suggests.

Study limitations. Retrospective, single health system. Prevalence set artificially to 5%, so absolute predictive values vary with the prevalence of the population tested.

What a false flag actually costs

Every flag triggers a workup: bone-tracer scintigraphy, serum and urine immunofixation, free light chains, sometimes biopsy or genetic testing. False flags consume nuclear cardiology capacity and clinic slots, and they expose patients to tests they did not need.

At 99.0% specificity

~10 false flags per 1,000 studies

The operating point InVision Precision Cardiac Amyloid is cleared at.

At 90% specificity

~100 false flags per 1,000 studies

An illustrative operating point: ten times the downstream workup for the same 1,000 studies.

Both halves are true. A high-specificity operating point finds fewer cases and generates far fewer unnecessary workups. Which balance suits your service depends on your nuclear cardiology and amyloid clinic capacity. See the simulated comparison →

Subgroups and fairness

In the FDA validation, subgroup analyses across age, gender, BMI, race/ethnicity, amyloidosis type, site, and imaging manufacturer all met the acceptance criteria. The Northwestern study also ran a bias audit.

Met the criterion

Equal opportunity ratio 1.05

Met the study's equal opportunity criterion for patients who self-identified as Black, statistically significant for parity. ATTR-CM prevalence in that group was about five times higher than in other groups in this cohort.

Flagged as a disparity

Demographic parity 0.64

Flagged by the paper as a disparity under the 80% rule. Published here alongside the favourable result.

We publish the flagged metric next to the favourable one. An AI governance committee that only ever sees a vendor's good number has learned nothing about the vendor.

Why the same model reports different AUCs

You will see several numbers for this model: 0.83 internal and 0.79 external in 2022, 0.88 in the Northwestern heart-failure cohort, 0.893 across five international sites, and 0.833 to 0.944 by individual site. That spread is not instability. It is cohort construction.

InVision published the paper that demonstrates this. In Impact of Case and Control Selection on Training Artificial Intelligence Screening of Cardiac Amyloidosis (JACC: Advances, 2024), model AUCs ranged from 0.660 to 0.898 on matched held-out test sets, and from 0.467 to 0.898 in a general patient population — varying by nothing except how cases and controls were selected.

An AUC is a property of a model and a cohort, not of a model alone. Comparing an AUC from one study against an AUC from another study with different case and control selection is not a valid comparison.

Provenance and open science

The model family behind Precision Cardiac Amyloid was developed and published in the peer-reviewed literature, and the underlying dataset was released publicly. Other research groups have tested it and published what they found.

JAMA Cardiology 2022Value
Patients23,745
Training videos24,804 echocardiogram videos
Cardiac amyloidosis classification AUC0.83
Hypertrophic cardiomyopathy AUC0.98
External validation, amyloidosisAUC 0.79
External validation, HCMAUC 0.89
Wall thickness mean absolute error1.4 mm (95% CI 1.2–1.5)
LV diameter mean absolute error2.4 mm (95% CI 2.2–2.6)
Posterior wall mean absolute error1.2 mm (95% CI 1.1–1.3)
Open dataset released23,212 annotated echocardiogram videos

These figures are provenance, not current performance. They are superseded by the 2025 international validation above.

What this device does not do

InVision Precision Cardiac Amyloid is decision-support AI. It does not diagnose.

Confirmation requires bone-tracer nuclear imaging, monoclonal gammopathy testing, genetic testing, and/or tissue biopsy. The software produces a structured starting point; a physician authors and signs every report.

Sensitivity at the cleared operating point is 60.7%. A negative result does not exclude cardiac amyloidosis. The intended population is adults aged 65 and older.

Both validations described on this page are retrospective case-control studies. Predictive values shift with the prevalence of the population actually tested, which is why the table in Reading sensitivity and specificity shows a range.

Citations

1. Published in the peer-reviewed literature as EchoNet-LVH. EchoNet-LVH and InVision Precision Cardiac Amyloid are the same model — the literature uses the research name, the FDA clearance uses the product name. Every external validation of EchoNet-LVH is therefore an external validation of the cleared device.

  1. Duffy G, Oikonomou EK, Easton N, Usuku H, Patel J, Katsumata Y, Yamasawa D, Stern L, Goto S, Tsujita K, Cheng P, Khera R, Ahmad FS, Ouyang D. International Validation of Echocardiographic Artificial Intelligence Amyloid Detection Algorithm. JACC: Advances. 2025. doi:10.1016/j.jacadv.2025.102067 ↗
  2. Hourmozdi J, Easton N, Benigeri S, Thomas JD, Narang A, Ouyang D, Duffy G, Upton R, Hawkes W, Akerman A, Okwuosa I, Kline A, Kho AN, Luo Y, Shah SJ, Ahmad FS. Evaluating the Performance and Potential Bias of Predictive Models for Detection of Transthyretin Cardiac Amyloidosis. JACC: Advances. 2025;4(8). doi:10.1016/j.jacadv.2025.101901 ↗
  3. Duffy G, Cheng PP, Yuan N, et al. High-Throughput Precision Phenotyping of Left Ventricular Hypertrophy With Cardiovascular Deep Learning. JAMA Cardiology. 2022;7(4):386–395. doi:10.1001/jamacardio.2021.6059 ↗
  4. InVision and collaborators. Impact of Case and Control Selection on Training Artificial Intelligence Screening of Cardiac Amyloidosis. JACC: Advances. 2024. doi:10.1016/j.jacadv.2024.100998 ↗

Questions about the evidence?

Our clinical team will walk through any figure on this page, including the ones where we score lower, and what the operating point means for your service.

We reply within one business day.
Figures render from _data/claims.json · Last reviewed October 2026.