An improved way to set up a more accurate presumptive diagnosis of cardiac amyloidosis
A Vereckei, H Takacs, G Fogarassy, Z Varga, G Katona, G Szenasi, D L Vidacs, V Nagy, R SeppAbstract
Background
The early diagnosis of cardiac amyloidosis (CA) is paramount, since there are effective therapies that improve patient survival. In a previous study our novel electrocardiographic (ECG) criteria for cardiac amyloidosis (CA) were much more accurate than the classical ECG criteria, such as low voltage and pseudoinfarct pattern, and had the same diagnostic value as that of the myocardial deformation criteria based on literature data.
Purpose
In this study we compared the diagnostic value of the myocardial deformation criteria measured by ourselves with that of the novel ECG criteria.
Methods
53 verified CA patients (41 transthyretin and 12 AL CA) and 50 control patients with left ventricular hypertrophy on echocardiography due to other underlying cause were studied. The following were the best tested criteria suggesting CA. 1. QRS amplitude in lead aVR <0.4 mV (aVR<0.4); 2. average QRS amplitude of leads I+aVR/average QRS amplitude of leads V1-4 <0.375 [(I+aVR)/(V1-4)<0.375]; 3. left ventricular posterior wall thickness/QRS amplitude in lead aVR >3.059 (PWT/aVR >3.059); 4. qualitative visual apical sparing (ApS); 5. quantitative average apical strain/average basal strain+average middle wall strain >1 [avApicS/(avBasS+avMidS) >1].
Results
The sensitivity, specificity, positive and negative predictive, test accuracy and area under curve values were the following. (aVR<0.4): 70%, 90%, 88%, 74%, 80%, 0.8711; [(I+aVR)/(V1-4)<0.375]: 60%, 92%, 89%, 69%, 76%, 0.7687; (PWT/aVR >3.059): 74%, 88%, 87%, 76%, 81%, 0.834; ApS: 86%, 70%, 75%, 83%, 78%, 0.7895; [avApicS/(avBasS+avMidS) >1]: 76.5%, 92%, 91%, 79%, 84%, 0.9073. These values of a 4-step algorithm with the greatest diagnostic accuracy composed of the 1., 3., 4., 5. criteria were: 91%, 82%, 84%, 89%, 86%, 0.8558, each of them was better than that of the ApS criterion. These values of the novel ECG and (PWT/aVR >3.059) criteria were approximately as accurate as those of the myocardial deformation criteria.
Conclusions
Based on our results, to establish a more probable presumptive CA diagnosis, in addition to the most commonly applied ApS criterion in clinical practice, it is recommended to use either the novel ECG and/or the (PWT/aVR >3.059) and/or the quantitative myocardial deformation criteria.