The First Harmonic of Radial Pulse as an Early Predictor of Silent Coronary Artery Disease and Adverse Cardiac Events in Type 2 Diabetic Patients

Abstract

Background It has been reported that harmonics of radial pulse is related to coronary artery disease (CAD) in patients with type 2 diabetes mellitus (T2DM). It is still unclear whether or not the first harmonics of the radial pulse spectrum is an early independent predictor of silent coronary artery disease (SCAD) and adverse cardiac events (ACE). Objectives To measure the risk of SCAD in patients with T2DM and also to survey whether or not an increment of the first harmonic (C1) of the radial pulse increases ACE. Methods 1968 asymptomatic individuals with T2DM underwent radial pulse wave measurement. First harmonic of the radial pressure wave, C1, was calculated. Next, the new occurrence of ACE and the new symptoms and signs of coronary artery disease were recorded. The follow-up period lasted for 14.7 ± 3.5 months. Results Out of 1968 asymptomatic individuals with T2DM, ACE was detected in 239 (12%) of them during the follow-up period. The logrank test demonstrated that the cumulative incidence of ACE in patients with C1 above 0.96 was greater than that in those patients with C1 below 0.89 (P < 0.01). By comparing the data of patients with C1 smaller than the first quartile and the patients with C1 greater than the third quartile, the hazard ratios were listed as follows: ACE (hazard ratio, 2.29; 95% CI, 1.55–3.37), heart failure (hazard ratio, 2.22; 95% CI, 1.21–4.09), myocardial infarction (hazard ratio, 2.44; 95% CI, 1.51–3.93), left ventricular dysfunction (Hazard ratio, 2.01; 95% CI, 0.86–4.70), and new symptoms and signs for coronary artery disease (hazard ratio, 2.03; 95% CI, 1.45–2.84). As C1 increased, the risk for composite ACE (P < 0.001 for trend) and for coronary disease (P < 0.001 for trend) also increased. The hazard ratio and trend for cardiovascular-cause mortality were not significant. Conclusions This study showed that C1 of the radial pulse wave is correlated with cardiovascular events. Survival analysis showed that C1 value is an independent predictor of ACE and SCAD in asymptomatic patients with T2DM. Thus, screening for the first harmonic of the radial pulse may improve the risk stratification of cardiac events and SCAD in asymptomatic patients although they had no history of coronary artery disease or angina-related symptom.

Risk assessment of macrovascular and microvascular events in patients with type 2 diabetes by analyzing the amplitude variation of the fourth harmonic component of radial pulse wave

“…Radial pulse waves were noninvasively measured by medical‐grade devices that had been found to be highly reproducible (Chang and Wang ), and the intra‐observer and inter‐observer reliabilities met the criteria for medical interpretation (Portney and Watkins ; Chang et al ). The standard operating procedures for environmental temperature control and radial pressure wave measurement were as described in previous studies (Chang et al , ). Before the measurement started, each patient was asked to rest for more than 5 min, keeping blood pressure as stable as possible.…”

“…The endpoint of coronary artery disease was defined as a new diagnosis of single coronary artery stenosis (≥70%), multiple coronary stenoses (≥50%), and ischemic myocardium (≥10%) for further cardiac examination. Definition of nonfatal myocardial infarction, hospitalization for heart failure, and diagnosis of coronary artery stenosis was detailed in previous studies (Chang et al ). The secondary interest outcomes were the composite endpoints of the microvascular events, composed of the major adverse kidney events (composite endpoints of double serum creatinine, end‐stage renal disease, kidney failure, and renal cause of death), macroalbuminuria, retinopathy, and polyneuropathy.…”

Applying Pulse Spectrum Analysis to Facilitate the Diagnosis of Coronary Artery Disease

“…Other studies also reported the factor of atherosclerosis [30, 31], or increasing afterload [29] will increase the first harmonic impedance which is related to the increasing burden of heart muscle. Chang et al reported that screening for the C1 may improve the risk stratification of cardiac events and silent coronary artery disease in asymptomatic patients [32]. Hence, the first harmonic amplitude increment could be a noninvasive risk marker for cardiovascular disease.…”

Pulse Wave Harmony: Ancient Wisdoms for Modern Age

“…where Ω is the bandwidth of interest andP(ω) is an estimation of the energy-normalised power power of such signal. However, the relative power using ratios of harmonics is relevant and indeed contains known health information [35,[53][54][55]. In our work we will limit the number of harmonics to Nb H = 4 and we use the harmonic power ratios as features: H i,j = A H i /A H j for i, j = 0, .., Nb H with j > i.…”