Decreased likelihood of response to cardiac resynchronization in patients with severe heart failure.
OBJECTIVE
We hypothesized that a very advanced stage of dilated cardiomyopathy is associated with lower response to cardiac resynchronization therapy (CRT).


RESULTS
A consecutive cohort of 147 patients was studied before device implantation and at 12 months follow-up. All patients were in NYHA functional class III-IV and had left-ventricular (LV) systolic dysfunction (LV ejection fraction 24 +/- 7%) and a wide QRS (171 +/- 29 ms). A patient who was alive without heart transplantation and had improved by at least 10% in the 6 min walking test at 12 months follow-up was considered a clinical responder. Fifty-four patients (36%) did not respond to CRT (15 cardiac deaths, 4 heart transplantations). Quality of life indicators (>41 points), LV end-diastolic volumes (>200 mL) and mitral regurgitant orifice area (>16 mm(2)) at baseline were independent predictors of response to CRT. Patients were assigned 1 point for each predictive parameter. Patients with higher scores showed a significantly higher likelihood of non-response to CRT (chi(2) = 12 891, P = 0.005).


CONCLUSIONS
The results show that non-responder patients have a more advanced stage of the disease, which suggests that CRT should be indicated earlier in the disease process.
Vidal
Bàrbara
B
Thorax Clinic Institute, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi i Sunyer, University of Barcelona, Villarroel 136, 08036 Barcelona, Spain.
Delgado
Victoria
V
Mont
Lluís
L
Poyatos
Sílvia
S
Silva
Etelvino
E
Angeles Castel
María
M
Tolosana
José M
JM
Berruezo
Antonio
A
Brugada
Josep
J
Sitges
Marta
M
D000368:Aged; D002304:Cardiac Pacing, Artificial; D015331:Cohort Studies; D016001:Confidence Intervals; D018450:Disease Progression; D005260:Female; D006333:Heart Failure / Q000000981:diagnostic imaging / Q000628:therapy*; D006801:Humans; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D016017:Odds Ratio; D011788:Quality of Life; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D013997:Time Factors; D016896:Treatment Outcome; D014463:Ultrasonography; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging / Q000628:therapy*