The calculator in question is the European Society of Cardiology (ESC) Diagnostic Criteria for Dilated Cardiomyopathy in Relatives. This calculator is specifically designed for the relatives of patients diagnosed with dilated cardiomyopathy (DCM). 

The clinical utility of this calculator is to identify the likelihood of a relative developing DCM based on their familial relationship to a diagnosed patient. It helps in early detection and intervention, potentially preventing the progression of the disease. 

The ESC Diagnostic Criteria for Dilated Cardiomyopathy in Relatives is not applicable to individuals without a family history of DCM. It also may not be suitable for use in individuals with other pre-existing heart conditions, as these could confound the results.

ESC diagnostic criteria for dilated cardiomyopathy in relatives

# Criteria
 # Major criteria
A. Unexplained decrease of left ventricular ejection fraction <= 50% but > 45% (+6)
B. Unexplained left ventricular end-diastolic dilatation (diameter or volume) according to nomograms (left ventricular end-diastolic diameter/volume > 2 standard deviations + 5%) (+6)
# Minor criteria
C. Complete left bundle branch block, or atrioventricular block (PR > 200 ms or higher degree atrioventricular block) (+1)
D. Unexplained ventricular arrhythmia (> 100 ventricular premature beats per hour in 24 hours or non-sustained ventricular tachycardia, >= 3 beats at a rate of >= 120 beats per minute) (+1)
E. Segmental wall motion abnormalities in the left ventricle in the absence of intraventricular conduction defect (+1)
F. Late enhancement of nonischemic origin on cardiac magnetic resonance imaging (+1)
G. Evidence of nonischemic myocardial abnormalities (inflammation, necrosis, and/or fibrosis) on endomyocardial biopsy (+1)
H. Presence of serum organ-specific and disease-specific anti-heart antibodies by >= 1 autoantibody tests (+1)
# Carrying the causative mutation identified in the proband
I. Yes (+1)
J. No (+0)

# Conditions
- score >= 7
- score >= 2
- true
- score == 0

Proposal for a revised definition of dilated cardiomyopathy, hypokinetic non-dilated cardiomyopathy, and its implications for clinical practice: a position statement of the ESC working group on myocardial and pericardial diseases.