Description

This is longitudinal data on an observational study on detecting effects of different heart valves, differing on type of tissue, implanted in the aortic position. The data consists of longitudinal measurements on three different heart function outcomes, after surgery occurred. There are several baseline covariates available, and also survival data.

Usage

Format

This is a data frame in the unbalanced format, that is, with one row per observation. The data consists in columns for patient identification, time of measurements, longitudinal multiple longitudinal measurements, baseline covariates, and survival data. The column names are identified as follows:

num

number for patient identification.

sex

gender of patient (0=Male and 1=Female).

age

age of patient at day of surgery (years).

time

observed time point, with surgery date as the time origin (years).

fuyrs

maximum follow up time, with surgery date as the time origin (years).

status

censoring indicator (1=died and 0=lost at follow up).

grad

valve gradient at follow-up visit.

log.grad

natural log transformation of grad.

lvmi

left ventricular mass index (standardised) at follow-up visit.

log.lvmi

natural log transformation of lvmi.

ef

ejection fraction at follow-up visit.

bsa

preoperative body surface area.

lvh

preoperative left ventricular hypertrophy.

prenyha

preoperative New York Heart Association (NYHA) classification (1=I/II and 3=III/IV).

redo

previous cardiac surgery.

size

size of the valve (millimeters).

con.cabg

concomitant coronary artery bypass graft.

creat

preoperative serum creatinine (μmol/mL).

dm

preoperative diabetes.

acei

preoperative use of ace inhibitor.

lv

preoperative left ventricular ejection fraction (LVEF) (1=good, 2=moderate, and 3=poor).

emergenc

operative urgency (0=elective, 1 = urgent, and 3=emergency).

hc

preoperative high cholesterol (0=absent, 1 =present treated, and 2=present untreated).

sten.reg.mix

aortic valve haemodynamics (1=stenosis, 2=regurgitation, 3=mixed).

hs

implanted aortic prosthesis type (1=homograft and 0=stentless porcine tissue).

References

Lim E, Ali A, Theodorou P, Sousa I, Ashrafian H, Chamageorgakis T, Duncan M, Diggle P, Pepper J. A longitudinal study of the profile and predictors of left ventricular mass regression after stentless aortic valve replacement. Ann Thorac Surg. 2008; 85(6): 2026-2029.

See Also

pbc2, renal, epileptic.qol.