Evaluation of Cardiopulmonary Function in SMON Patients at the Mass Examination in Japan.

Abstract

The purpose of this study was to investigate autonomic disorder of the cardiopulmonary system of patients who were diagnosed as hypoventilation according to coefficient of variation of R-R (CVR-R) in electrocardiograms of SMON (subacute myelo-optico-neuropathy) patients at mass examinations in many regions of Aichi Prefecture in Japan. One hundred twenty two patients, diagnosed as SMON ranging in age from fifty one to eighty eight (mean 72.1) participated. As investigation items, ventilation capability (%VC, %FVC, FEVl%, %MMF, V50 and V25) and CVR-R (during deep breathing load) were measured. The following results were obtained: 1) Ventilation functions among patients: those who had %VC of equal or less than 80%, or those who had FEVl% of equal or less than 70% were 44 cases (36.1%). 2) CVR-R during deep breathing: SMON patients were divided into two groups of ventilation capability normal group and depression group. During deep breathing, significantly higher values than at the resting time were shown in ages equal and below seventy of ventilation capability depression group. Based on the above results, among ventilation capability depression group, disturbance of activities of parasympathetic nerve system was estimated to exist, because CVR-R showed lower values then those of normal group at the resting, while it showed a significant increase at the time of deep breathing load.