Predictors of Functional Capacity in Chronic Heart Failure: Echocardiography Versus Six-Minute Walk Test

Abstract

Background: Six-minute walk test (6MWT) constitutes a suitable alternative for Cardio-pulmonary exercise testing to assess functional capacity in patients with heart failure (HF). Echocardiography has always been considered as the most useful easy test for evaluation of these patients.

Proposed method for evaluation and categorization of functional capacity of children, adolescents, and adults with cardiac diseases to bring them in existing social justice system by creating the cardiac disability criteria

“…Scores from CDS-objective criteria [12,13,[41][42][43][44][45][46][47][48][49][50][51][52] (maximum score = 40) + 10 Basal ECG or Holter monitoring (± abnormal imaging echo/CT/MRI/PET/cardiac cath) suggestive of significant ischemia, strain, severe ventricular hypertrophy or rhythm disorders, channelopathies, needing intervention; ECHO/CT/MRI (± ECG changes) suggestive of HD (structural, coronary or vascular or pericardial or tumor) associated with serious hemodynamic effects due to anatomical/functional abnormalities; pre/post-intervention HD presenting with functional abnormalities(+ regional wall motion abnormality, LV function < 40%, high PA pressure > mean 40 mmHg/PVRI > 6 woods unit, RV Dysfunction by existing criteria-TAPSE less than expected age-appropriate value; Fr. area shortening = < 30%), ± significant residual lesions or systemic hypertension + 10 6-min walk test < 400 m (≃abnormal exercise test, MET< 7, V2Max < 14 ml/kg/min/) ± abnormal stress test (TMT/echocardiogram/thallium test) in presence of HD with significant hemodynamic challenges (exercise, stress test must not be done in critical diseases) + 10 For evidence of clinical HF(systemic congestion-raised JVP/hepatomegaly, pedal edema or pulmonary congestion/crepts/pulmonary edema, basal tachycardia, bradycardia, or chronotropic incompetence* (abnormal chronotropic index (< 0.8 and > 1.3) -peak HR/resting HR)/(220age/resting HR) resulting into radiological HF (cardiomegaly, pulmonary edema, PAH/PVH); biochemical markers of HF (NT-proBNP > 1700 pg/mL or BNP > 140 pg/mL) or systemic hypoxia = Hct > 55% in presence of cyanosis + 10 Hospital admission records-documenting palliative procedure/cardiac syncope, E/O tachy-or bradyarrhythmia, chronotropic incompetence;…”

“…Objective criteria-elicitation of relevant tests and diligent verification of hospital records Table 3 shows a systematic approach to assess FC objectively based on existing parameters described in literature [12][13][14][44][45][46][47][48][49][50][51][52]. Examination of longitudinal meticulously kept medical records gives information about the frequency and duration of hospitalization, basal saturation and need for oxygen therapy, polycythemia, documented episodes of syncope and other cardiac events, systemic congestion of cardiac origin, capacity to exercise, episodic elevation of cardiac enzymes and abnormal electrocardiograms, cardiac interventions, need for temporary or permanent pacemaker implantation, co-existing illnesses, and response to medical management.…”

“…Nevertheless, functional capacity as we know is the ability to initiate and sustain accustomed and unaccustomed exercise, indicating the efficiency of the integrated functioning of the cardiovascular-pulmonary unit, in the presence of a cardiac disease [19][20][21][22][23][24][25][26][27][28][29]. Determination of peak VO2/ METs in response to exercise (submaximal treadmill or bicycle exercise testing) or 6-, 9-, and 12-min walk tests are the objective methods described in the literature to assess FC of a patient with the compromised cardiac status [44][45][46][47][48][49][50]. High level of Nterminal pro BNP (NT-proBNP) and B-type natriuretic peptide (BNP) levels have been used to grade severity of CHF in the modified Ross classification of HF [42].…”