ASN 36th Annual Meeting & Scientific Exposition

Filename: 553868

Presenting Author: Aldo J Peixoto

Department/Institution: Medicine/Nephrology, Yale University and VA Connecticut

Address: Renal 111F, 950 Campbell Avenue

City/State/Zip Code/Country: West Haven, CT, 06516, United States

Phone: 203-932-5711 x5907 Fax: 203-937-3455 E-mail: aldo.peixoto@yale.edu Member Number: 104212

Potential Conflict of Interest: Yes,
Grants/Research Support: Pulsemetric Inc provided the Dynapulse 500G device free of charge as well as free use of the Dynapulse Analysis Center (www.dynapulse.com)

Abstract Category: 302 Hemodynamics, Hypertension and Vascular Regulation: Hypertension - Clinical

Entities that provided funding for this abstract:
Clinical Revenue Support

Sponsor:

Institution: E-mail: Member Number:

Keywords:
Vascular Changes; Chronic Kidney Disease; Hypertension

Title: Arterial Compliance (AC) in Elderly Men with Chronic Kidney Disease (CKD): Impact of Blood Pressure (BP) and Renal Function
Aldo J Peixoto, MD ¹*, Ambreen Hussain MD ² and Shaheen Motiwala MBBS ². ¹ Medicine/Nephrology, Yale University and VA Connecticut, New Haven, CT, United States and ² Medicine, University of Connecticut, Farmington, CT, United States .
Abstract:

Decreased AC predicts death in end-stage kidney disease (ESKD). The temporal relationship between loss of glomerular filtration rate (GFR) and impairment of AC is not known, especially in older patients. We measured AC via analysis of brachial artery (BA) oscillations in 65 men aged >60 years. Subjects were divided in 3 groups: G1=stage III-IV CKD (N=43, age 75+8, GFR 34+12), G2=ESKD on chronic hemodialysis (N=8, age 73+8, GFR negligible), and G3=controls (N=14, age 72+8, GFR 76+9). AC parameters included BA compliance (BAC) and distensibility (BAD), systemic vascular compliance (SVC), brachial BP and calculated central BP. All groups had decreased AC. When we divided G1 in tertiles of GFR (T1,T2,T3), analysis of variance (ANOVA) did not show differences in AC parameters among the tertiles, G2 and G3 (table), and no significant correlation was noted between GFR and AC parameters for the entire group. No differences were observed in many clinical and biochemical parameters of relevance to AC. A multiple regression model including age, body weight, GFR, central SBP and PP demonstrated that only central SBP and PP were independent predictors of AC parameters in this population. In conclusion, these data show no significant relationship between GFR and AC that is independent of distending pressure in elderly men with CKD. The implications for cardiovascular risk assessment in these patients require further study.

Vascular Parameters According to GFR group
	CKD T1	CKD T2	CKD T3	ESKD	Controls	ANOVA (P)
Brachial BP	142/77+13/8	140/79+14/12	141/77+20/12	150/74+17/14	138/75+12/8	0.52/0.85
Brachial PP	65+9	62+16	64+12	73+19	63+13	0.45
Central BP	160/71+18/7	157/69+17/8	157/73+18/14	154/77+11/8	155/71+11/7	0.91/0.42
Central PP	88+18	88+18	84+13	76+12	85+13	0.46
BAC (ml/mmHg)	0.05+0.02	0.05+0.16	0.06+0.13	0.06+0.02	0.05+0.01	0.66
BAD (%/mmHg)	3.96+1.05	3.77+0.89	4.07+1.06	4.49+1.20	3.90+0.61	0.53
SVC (ml/mmHg)	0.99+0.25	0.96+0.30	0.93+0.15	1.16+0.30	0.92+0.16	0.22

ASN 36th Annual Meeting & Scientific Exposition

Filename: 550934

Presenting Author: Shaheen Motiwala

Department/Institution: Medicine/Nephrology, Yale University and VA Connecticut

Address: Renal 111F c/o Dr. Aldo Peixoto, 950 Campbell Avenue

City/State/Zip Code/Country: West Haven, CT, 06516, United States

Phone: 203-932-5711 x5907 Fax: 203-937-3455 E-mail: shaheenmotiwala@hotmail.com Member Number:

Potential Conflict of Interest: Yes,
Grants/Research Support: Pulsemetric Inc. provided research support in the form of free loan of the Dynapulse 500G device and free use of the Dynapulse Data Analysis Center (www.dynapulse.com).

Abstract Category: 206 Dialysis: Complications of Hemodialysis

Entities that provided funding for this abstract:
Clinical Revenue Support

Sponsor: Aldo Peixoto

Institution: Yale University E-mail: aldo.peixoto@yale.edu Member Number: 104212

Keywords:
Hemodynamics; Hemodialysis Complications; Cardiac Function

Title: Reliability of a Non-Invasive Device to Estimate Systemic Hemodynamics in Hemodialysis Patients
Shaheen Motiwala MBBS ¹, Ursula C Brewster, MD ², Mark A Perazella, MD ²* and Aldo J Peixoto, MD ²*. ¹ Department of Medicine, University of Connecticut School of Medicine, Farmington, CT, United States and ² Section of Nephrology, Yale University and VA Connecticut, New Haven, CT, United States .
Abstract:

Monitoring of systemic hemodynamic parameters (SHP) in hemodialysis (HD) may improve the management of hypotenson/hypertension, but methods to measure SHP in dialysis are specialized, time-consuming or expensive. A non-invasive method based on brachial artery oscillations recorded with a conventional BP cuff has been developed and validated in non-HD patients. Herein we present data on its reliability in 15 stable HD patients (all male, age 63+12). BP and SHP were obtained with the Dynapulse 500G device (Pulsemetric Inc., San Diego, CA). Measurements were sequential, in duplicate, pre, trans and post-HD, in the supine, seated and standing positions on four HD sessions over 2 weeks. Waveforms were downloaded to a computer with device-specific software. The repeatability of the method was tested using 200 pairs of measurements. Each value was compared with its pair, and Bland-Altman plots were created using the mean difference (without sign) and SD of the differences (SDD) to establish 95% limits of agreement (95% LA = mean diff+1.96SDD). As shown on the table, narrow 95% LA indicate good reliability of the device for all measured SHP. The figure displays the agreement for cardiac index (CI); similar patterns were observed for all SHP.We conclude that the Dynapulse 500G has adequate reliability indices in HD patients. Further research is needed to assess its value in clinical dialysis practice.

Reliability of Systemic Hemodynamic Parameters
	Mean (SD)	Difference (SD diff)	95% LA
LV dp/dt max (mmHg/sec)	1320 (268)	157 (173)	-182, 496
SV(ml)	70 (13)	3.6 (3.4)	-3, 10
CO (L/min)	5.3 (1.0)	0.33 (0.39)	-0.4, 1.1
CI (L/min)	2.8 (0.5)	0.18 (0.20)	-0.2, 0.6
SVR (dynes/sec/cm5)	1455 (359)	128 (123)	-113, 369