Acute Effects of Caffeine on Arterial Stiffness in Young Healthy Subjects

BACKGROUND AND OBJECTIVES: Coffee is one of the most popular beverages in the world. Caffeine is one of the substances contained in coffee and it is well known to increase blood pressure and the peripheral vascular resistance, in part because it stimulates the sympathetic nervous system. Arterial stiffness is an important factor for the performance of the cardiovascular system and it is an independent prognosticator of cardiovascular disease. We investigated the acute effect of caffeine on arterial stiffness in young healthy subjects. SUBJECTS AND METHODS: We enrolled 20 young healthy subjects, who were randomly divided two groups. The caffeine group (10 subjects, 4 males, mean age: 23.3+/-1.1 years) received 520 mL caffeinated coffee and the control group (10 subjects, 4 males, mean age: 23.1+/-1.3 years) received 520 mL water. The arterial stiffness was evaluated by the carotid-radial pulse wave velocity and the augmentation index as corrected by heart rate (75 bpm), and all the hemodynamic measurements were obtained at baseline, 30, 60, 120 and 180 minutes after ingestion of the coffee or water. RESULTS: Arterial stiffness measured by carotid-radial pulse wave velocity increased progressively from 9.4+/-1.2 m/sec at baseline to 11.5+/-1.6 m/sec (p<0.05) at 30 minutes after the coffee intake. In addition, peripheral systolic pressure increased progressively from 107.1+/-10.2 mmHg at baseline to 114.4+/-12.9 mmHg (p<0.05) at 60 minutes after the coffee intake. Such changes were not seen in control group. CONCLUSION: Caffeine affects increased the pulse wave velocity and systolic blood pressure. This means that coffee might have an adverse effect on arterial stiffness.

The Relationship of Left Atrial Volume and Left Ventricular Diastolic Dysfunction

BACKGROUND AND OBJECTIVES: Mitral flow Doppler has been used to evaluate left ventricle (LV) diastolic function by mitral E/A flow ratio, isovolumic relaxation time (IVRT) and deceleration time (DT) of E wave. Such variables can be affected by various factors. The increase in left atrium (LA) afterload and preload is accompanied by increased LA size. So, we investigated the relationship of LA volume and LV diastolic dysfunction. MATERIALS AND METHOD: From January 2000 to July 2000, 39 patients were included in this study. They were classified into normal (M:F=5:6, mean age 54.0+/-11.4 years), impaired relaxation (M:F=5:4, mean age 70.0+/-5.5 years), pseudonormal (M:F=5:3, mean age 68.3+/-13.2 years) and restrictive physiology (M:F=10:1, mean age 65.5+/-12.7 years) according to mitral inflow variables. The LA volume of each groups was measured by Simpson method, M-mode method and arealength method. RESULTS: 1) The LA volumes measured by Simpson method, M-mode method and area-length method were correlated (p<0.001, r=0.925 in Simpson compared with arealength method). 2) The LA volume by Simpson method were found 54.4+/-16.4 cm3 in normal, 57.3+/-9.2 cm3 in impaired relaxation, 81.4+/-28.8 cm3 in pseudonormal and 119.8+/-64.5 cm3 in restrictive physiology. 3) The LA volume were significantly increased in pseudonormal group compared with normal (p<0.05). CONCLUSION: The LA volume is a useful and easy diagnostic stool for evaluating of LV diastolic function.

Intracardiac Electrogram at Successful Site of Radiofrequency Catheter Ablation in Patients with Atrioventricular Nodal Reentrant Tachycardia

BACKGROUND AND OBJECTIVES: Ablation of the slow pathway in patients with atrioventricular nodal reentrant tachycardia (AVNRT) can be performed by using a specific intracardiac electrogram findings predicting a successful radiofrequency catheter ablation. The purpose of the present study is to recognize a specific intracardiac electrogram findings predicting a successful sites of radiofrequency catheter ablation in patients with AVNRT. MATERIALS AND METHODS: The study population consisted of the 18 patients (7 males, mean age:46 yr) to undergo successful catheter ablation using radiofrequency current in order to eliminate AVNRT from January 1993 to september 1994. We have analyzed local intracardiac electrogram at successful and unsuccessful sites of radiofrequency catheter ablation before the radiofrequency application: Atrial electrogram amplitude, duration, number of peaks in atrial electrogram, atrial/ventricular (A/V) electrogram amplitude ratio, and presence of His potential and/or slow potential. RESULTS: Of 18 patients, 16 patients underwent a slow pathway ablation, the other 2 patients a fast pathway ablation. The mean A/V electrogram amplitude ratio at successful and unsuccessful sites was 0.69+/-0.91 and 1.86+/-2.03, respectively. The mean atrial electrogram duration and number of peaks at successful and unsuccessful sites was 57+/-16 msec vs 69+/-16 msec and 1.7+/-0.5 vs 2.2+/-0.7, respectively. His bundle electrogram was seen in one slow pathway ablated and one fast pathway ablated patient. No slow potential could be identified in any of these 18 patients. CONCLUSION: We think that A/V electrocardiogram amplitude ratio below 0.5 at posterior interatrial septum along tricuspid annulus is important marker indicating a successful ablation sites.

Diastolic Function Evaluation in Systemic Arterial Hypertension : A Color M-mode Doppler and Doppler Echocardiographic Analysis

BACKGROUND: Several recent studies have demonstrated that left ventricular diastolic dysfunction is major cause of congestive heart failure and may precede systolic dysfunction or without left ventricular hypertrophy in most patients with systemic arterial hypertension. The purpose of this study is to evaluate left ventricular diastolic function in patients with systemic arterial hypertension compared with normal control group using color M-mode Doppler and Doppler echocardiographic studies. METHODS: From October 1994 to August 1995. 53 patients(18 men and 35 women, mean age : 56.1±12.6 years) with essential hypertension and 30 subjects age-matched nomal controls(13 men and 17 women, mean age 55.9±12.3 years) were included in this study. We measured the early propagation slope of LV inflow by color M-mode Doppler Echocadiography and the peak velocities of E and A wave, E/A tatio, deceleration time of E wave, isovolumic relaxation time by Doppler echocardiography. We also studied left ventricular diastolic function in patients with hypertension who were divided two group(Group I : hypertension with left ventricular hypertrophy, Group II : hypertension without left vetricular hypertrophy). RESULTS: 1) Early propagation slope of LV inflow was significantly decreased in patients with hypertension compared with normal control group(57.43±17.15m/secs vs 69.87±12.71m/secs, p 0.05), whereas deceleration time of E wave was showed increasing tendency in patients with hypertension empared with normal control group(196.57±37.07m/secs vs 189.33±41.35m/secs, p>0.05). 3) Early propagation slope of LV inflow was not significantly different between Group I and Group II, but showing decreasing tendency in Group I compared with Group II(54.72±14.65m/sec vs 60.16±18.96m/sec, p>0.05). Peak velocity of E wave and peak velocity of A wave and E/A ratio and deceleration time were not significantly different between Group I and Group II but peak velocity of E wave and E/A ratio were showed decreasing tendency in Group I(0.65±0.19m/sec vs 0.73±0.22m/sec, 0.86±040 vs 1.04±0.44, p>0.05), whereas peak velocity of A wave and deceleration time of E wave were showed increasing tendency in Group I(0.80±0.20m/sec vs 0.74±0.18m/sec, 199.38±46.45m/secs vs 196.89±24.76m/secs, p>0.05). Only isovolumic relaxation time was significatly increased in Group I compared with Group II(150.63±44.75m/secs vs 120.34±19.77m/secs, p < 0.05). CONCLUSION: Left ventricular diastolic dysfunction may precrede systolic or without left ventricular hypertrophy in patients with systemic arterial hypertension. An early diagnosis of left ventricular diastolic dysfunction, color M-mode Doppler echocardiography and Doppler echocardiography were useful diagnostic stools.

Colonoscopic Experience in 3 Cases of Primary Colonic Lymphoma / 대한소화기내시경학회지

Primary colonic lymphoma is a rare disease and open surgical biopsy is usually necessary for hietological confirmation. Despite the submucosal location of the tumors, histological confirmation is frequently made by endoscopic multiple punch biopsies. Recently, three patients were admitted to the hospital with right lower guadrant abdominal pain, mass and abnormalities in the right colon and cecum on the barium enema. We performed colonoscopy and found smooth surfaced polypoid mass with occasional shallow ulcerations without lobulation, so suspected lymphoma endoscopically but failed to confirm histologieal diagnosis by usual punch biopsy. Thereafter, all three cases were undergone to laparntomies, and two were confirmed to be non-Hodgkins lymphoma and the other was Hodgkins disease. Here, we present those three cases of endoscopically found colonic lymphoma with review of literatures.