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Biomedical subjects

C W Kong

Publications and source records attributed to C W Kong.

At least 37 records · Page 2Linked to original sources

Hemodynamic mechanism of vasovagal syncope.

Vasovagal syncope is a common clinical problem, however the hemodynamic mechanism is not clearly understood. The aim of the present study was to investigate the circulatory control mechanism of vasovagal syncope provoked by the head-up tilt test. Thirty two patients with recurrent unexplained syncope were studied using a head-up (60 degrees) tilt test. The electrocardiogram, arterial blood pressure, pulmonary arterial pressure and central venous pressure were monitored continuously, and the cardiac output was measured by the thermodilution method. Twenty patients (62.5%) had positive tilt test responses, of which 12 developed typical vasovagal syncope with marked hypotension and bradycardia; the others developed hypotension without bradycardia. There were five women and seven men with a mean age (+/- SD) of 53.3 +/- 15 years. The effect of head-up tilt resembled that of hypovolemia. The central venous pressure, pulmonary capillary wedge pressure and cardiac output declined with an increase of heart rate and systemic vascular resistance. However the mean blood pressure was maintained. During vasovagal syncope, the heart rate and blood pressure fell precipitously and significantly, the cardiac index was reduced from 2.22 +/- 0.43 to 1.51 +/- 0.32 liters/min/m2 (p value < 0.05) and the systemic vascular resistance index decreased from 3,689 +/- 859 to 1,999 +/- 543.9 dynes s cm5/m2 (p value < 0.05). The results of our study showed that both reduction of cardiac output and withdrawal of sympathetic vasoconstriction tone contribute to the development of hypotension in vasovagal syncope.

Adult↗

Sequential hemodynamic changes for large volume paracentesis in post-hepatitic cirrhotic patients with massive ascites.

Large volume paracentesis (4.8 to 15.5 liters) was performed in 42 patients with post-hepatitic cirrhosis and massive ascites, not only to derive parameters capable of predicting the development of severe clinical hypotension after large volume paracentesis, but also to determine the optimal time to introduce preventive volume expanders. Systemic hemodynamics were sequentially measured for 72 hours in thirty-two patients. Severe clinical hypotension occurred in 13 (31.0%) patients 4-62 hours from the start of paracentesis. Univariate analysis, with the Mantel-Cox test used to compare Kaplan-Meier curves, and the subsequent multivariate analysis by stepwise Cox regression procedure were utilized to identify two variables, withdrawn ascitic fluid greater than 7.5 liters (p = 0.0121) and the absence of peripheral edema (p = 0.0148), reaching statistical significance to predict the occurrence of severe clinical hypotension. Compared to the baseline value, the cardiac output of patients not developing severe clinical hypotension increased (6.26 +/- 0.66 vs. 6.65 +/- 0.69 liter/min, p < 0.01) one hour from the start of paracentesis and right atrial pressure decreased (11.2 +/- 2.4 vs. 8.7 +/- 2.3 mmHg, p < 0.05). The cardiac output returned to the baseline value at the 9th hour. Based on the results presented herein, we can conclude that severe clinical hypotension occurs in a high percentage of patients with post-hepatitic cirrhosis and massive ascites within 72 hours from the start of large volume paracentesis. At potential risk of this occurring are those patients without peripheral edema and withdrawn ascitic fluid greater than 7.5 liters. Volume expanders should be introduced before 4th hour from the start of large volume paracentesis.

Adult↗

Transvenous permanent left ventricular pacing. A case report.

This case report presents a patient who inadvertently received transvenous permanent left ventricular pacing through an unexpected atrial septal defect. This lead malpositioning was proved by two-dimensional and transesophageal echocardiography. The abnormal pattern of electric activation was demonstrated by radionuclide phase image analysis. He has been followed up for a total of forty-three months with antiplatelet therapy and has been free from systemic embolic phenomena. A simple and readily available method that could lead to early recognition of lead malpositioning is reiterated and the various causes, methods of detection, and prognosis of left ventricular pacing are discussed.

Aged↗

Atrial demand pacing in patients with symptomatic sick sinus syndrome.

Atrial demand pacing provides a physiological, simply implemented, and less costly alternative of cardiac stimulation in symptomatic sick sinus syndrome (SSS) patients. Hindrance from widespread use stems mainly from the potential development of high degree AV block and persistent atrial fibrillation. A reappraisal of atrial pacing is now justified as we gain more clinical information. In this study we examined retrospectively the clinical course of 22 well-selected SSS patients paced in AAI mode for 30 +/- 29 months. Two patients had infrequent short-run atrial tachyrhythmia before implantation. There was an early lead dislodgement which required repositioning later. Three acute threshold increments were noted which necessitated a change in atrial pacing site in one and short-term steroid use in the other two. No other sensing, pacing or operative complication occurred and all pacing systems performed well. AII patients survived during follow-up and no patient developed congestive heart failure, though depressed left ventricular function was found in three preoperatively. No high degree AV block was encountered. Four patients presented paroxysmal atrial fibrillation (PAF) 25 +/- 16 months after the procedure, of whom one developed chronic atrial fibrillation. No single factor predicted the development of PAF. Resumption of normal pacemaker function always occurred immediately in the pause following cessation of PAF and no revision of pacing mode was required in the patient with chronic AF. Symptomatic relief was obtained in all patients. In summary, single chamber, single rate atrial pacing remains a physiologic, reliable, economic and easily implemented pacing modality affordable to a number of sick sinus patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Right atrial pacing for risk stratification in patients with angina pectoris.

Right atrial pacing (RAP) has been used to assess the physiologic impact of coronary artery disease (CAD). Several variables have served as markers of pacing-induced myocardial ischemia or for predicting disease severity, but their clinical implications remain uncertain. Therefore, three-stage RAP was performed to evaluate whether this strategy could predict the disease severity of CAD and foretell subsequent major cardiac events in 49 patients with typical chest pain. RAP was considered positive if 1 mm or more of horizontal or downward ST depression developed. Of the 49 cases, 28 had positive RAP (group A), and the remaining 21 had negative RAP (group B). For hemodynamic data, early positive RAP had the highest post-pacing left ventricular end-diastolic pressure (LVEDP). The LVEDP increased significantly in Group A (p < 0.05), whereas there was no apparent change in group B. Furthermore, group A (36%) tended to develop typical chest pain more easily than group B (14%), but this was statistically insignificant. Group A had a higher incidence of multivessel disease than that of group B (p < 0.001), whereas group A had a lower incidence of non-significant CAD than that of group B (p < 0.001). During the mean two-year follow-up period, there were 23 major cardiac events (MCE) in group A in contrast to two episodes in group B (p < 0.005). The early positive subset had 18 episodes, whereas the late positive subset had only five episodes (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

Recurrent conduction in accessory pathway and possible new arrhythmias after radiofrequency catheter ablation.

Radiofrequency catheter ablation was performed in 142 patients with 166 accessory pathways. One hundred thirty-six patients with 160 accessory pathways underwent successful ablation in the first ablation session. Serial follow-up electrophysiologic studies were performed immediately (30 minutes), early (5 to 7 days), and late (3 to 6 months) after successful ablation to determine the recurrent accessory pathway conduction and possible new arrhythmias. After a minimum follow-up period of 6 months (mean, 14 +/- 3 months), accessory pathway conduction recurred in 13 patients (9.6%), with recurrent tachycardia in three patients (2.2%). Five of the recurrent accessory pathways had decremental conduction properties. Incidence of recurrent accessory pathway conduction was similar in different accessory pathway locations (6.4% to 9.0%). Patients with concealed accessory pathways (12.2 vs 2.9%; p < 0.05), and patients without accessory pathway potentials in the ablation site (15.5% vs 2.2%; p < 0.05) had a higher recurrence rate. Patients without tachycardia in the late electrophysiologic study did not have recurrent tachycardia during follow-up. New arrhythmias, including atrial and ventricular arrhythmias, which were detected by 24-hour Holter monitoring, were apparent only on the first day after ablation. The findings indicate that the overall incidence of recurrent accessory pathway conduction was low and that possible new arrhythmias were rare in the late follow-up period.

Adult↗

Comparison of direct-current and radiofrequency ablation of free wall accessory atrioventricular pathways in the Wolff-Parkinson-White syndrome.

To evaluate and compare the safety and efficacy of catheter-mediated direct-current (DC) or radiofrequency (RF) ablation in patients with free wall accessory atrioventricular pathways, 95 patients with free wall accessory atrioventricular pathway-mediated tachyarrhythmias underwent catheter ablation. Immediately after ablation, 27 of 30 accessory pathways (90%) were ablated successfully with DC, but 2 of the 27 had early return of conduction and received a second ablation session; 3 of 8 (38%) and 57 of 62 (92%) accessory pathways were ablated successfully with RF through a small-tip (2 mm) and a large-tip (4 mm) electrode catheter, respectively. Complications in DC ablation included transient hypotension (2 patients) and pulmonary air-trapping (2 patients) and in RF ablation, cardiac tamponade (1 patient) and suspicious aortic dissection (1 patient); myocardial injury and proarrhythmic effects were more severe in DC ablation. Procedure and radiation exposure time were significantly longer in RF ablation (DC, 3.6 +/- 0.2 hours, 34 +/- 4 minutes; RF 4.2 +/- 0.5 hours, 50 +/- 10 minutes). This study confirms that RF ablation is associated with little morbidity and few complications, and RF ablation with a large-tip electrode catheter is an effective and relatively safe nonsurgical method for treatment of free wall accessory atrioventricular pathway-mediated tachyarrhythmias.

Adult↗

Catheter ablation of accessory atrioventricular pathways in 114 symptomatic patients with Wolff-Parkinson-White syndrome--a comparative study of direct-current and radiofrequency ablation.

To evaluate and compare the safety and efficacy of catheter-mediated direct-current and radiofrequency ablation in patients with Wolff-Parkinson-White syndrome, 114 patients with accessory pathway-mediated tachyarrhythmias underwent catheter ablation. Electrophysiologic parameters were similar in patients undergoing direct-current (group 1, 52 patients with 53 accessory pathways) and radiofrequency (group 2, 62 patients with 75 accessory pathways) ablation. Immediately after ablation, 50 of 53 accessory pathways (94%) were ablated successfully with direct current, but 2 of the 50 accessory pathways had early return of conduction and required a second ablation; 72 of 75 accessory pathways (96%) were ablated successfully with radiofrequency current. In the three accessory pathways in which radiofrequency ablation was unsuccessful, a later direct-current ablation was successful. During follow-up (group 1, 14 to 27 months; group 2, 8 to 13 months), none of the patients with successful ablation had a recurrence of tachycardia. Complications in direct-current ablation included transient hypotension (two patients), accidental atrioventricular block (one patient), and pulmonary air trapping (two patients); complications in radiofrequency ablation included cardiac tamponade (one patient) and suspicious aortic dissection (one patient). Myocardial injury and proarrhythmic effects were more severe in direct-current ablation. The length of the procedure and the radiation exposure time were significantly shorter in direct-current (3.5 +/- 0.2 hours, 30 +/- 4 minutes) than in radiofrequency (4.1 +/- 0.4 hours, 46 +/- 9 minutes) ablation. Findings in this study confirm the impression that radiofrequency ablation is associated with fewer complications than direct-current ablation and radiofrequency ablation with a large-tipped electrode catheter is an effective and relatively safe nonsurgical method for treatment of Wolff-Parkinson-White syndrome.

Atrial Fibrillation↗

Reappraisal of electrical cure of atrioventricular nodal reentrant tachycardia--lessons from a modified catheter ablation technique.

A modified catheter ablation technique was studied prospectively in 29 patients with atrioventricular (AV) nodal reentrant tachycardia. A His bundle electrode catheter was used for mapping and ablation. Cathodic electroshocks (100-250 J) were delivered from the distal two electrodes (connected in common) of the His bundle catheter to the site selected for ablation. The optimal ablation site recorded the earliest retrograde atrial depolarization, simultaneous or earlier than the QRS complex, with absence of a His bundle deflection during AV nodal reentrant tachycardia. One additional electrical shock was delivered if complete abolition of retrograde VA conduction persisted for more than 30 min and AV nodal reentrant tachycardia was not inducible during isoproterenol and/or atropine administration. With a cumulative energy of 323 +/- 27 J and a mean of 2.3 +/- 0.5 shocks interruption or impairment of retrograde nodal conduction was achieved. Antegrade conduction, although modified, was preserved in 27 patients, with persistence of complete AV block in 2 patients. Two of the 27 patients still need antiarrhythmic agents to control tachycardia, the other 25 patients were free of tachycardia within a mean follow-up period of 13 +/- 2 months (range 7 to 20 months). Twenty-three patients received late follow-up electrophysiological studies (3-6 months after the ablation procedures), and the AV nodal function curves were classified into 4 types. The majority of the patients (15/23) had loss of retrograde conduction. Among the 8 patients with prolongation of retrograde conduction, 4 patients still had antegrade dual AV nodal property but all without inducible tachycardia. In conclusion, preferential interruption or impairment of retrograde conduction was the major, but not the sole, mechanism of electrical cure of AV nodal reentrant tachycardia.

Adult↗

Radiofrequency catheter ablation for treatment of Wolff-Parkinson-White syndrome--short- and long-term follow-up.

One hundred and twenty-five patients with accessory pathways mediated tachyarrhythmias underwent radiofrequency ablation. Right-sided accessory pathways were ablated from the atrial aspect of the tricuspid anulus (all from the femoral vein approach) and the left-sided accessory pathways were ablated from the atrial or ventricular aspect of the mitral anulus. Immediately after the procedures, 3 of 8 accessory pathways (38%) and 131 of 137 accessory pathways (95%) were ablated successfully with radiofrequency through a small-tip (2 mm) and a large-tip (4 mm) electrode catheter, respectively. Seven of the 11 accessory pathways that failed radiofrequency ablation had a later successful direct current ablation. During follow-up (3 to 22 months), serial electrophysiological study showed that 11 of the 114 patients (10%) with successful ablation had return of accessory pathway conduction (2 had recurrence of tachycardia, 2%). Complications included accidental AV block (1 patient), cardiac tamponade (1 patient) and possible aortic dissection (1 patient). Transient proarrhythmic effects (more atrial and ventricular premature beats) were seen during the first week and sustained ventricular tachyarrhythmias were not inducible. In a successful session, procedure and radiation exposure times (including the time for diagnostic procedures) were 3.8 +/- 0.2 h and 45 +/- 4 min, respectively. This study confirms that radiofrequency ablation with a large-tip electrode catheter is an effective and relatively safe nonsurgical method for treatment of Wolff-Parkinson-White syndrome, with a low complication and recurrence rate.

Adult↗

Catheter ablation of free wall accessory atrioventricular pathways in 89 patients with Wolff-Parkinson-White syndrome--comparison of direct current and radiofrequency ablation.

To evaluate and compare the safety and efficacy of catheter-mediated direct current (DC) or radiofrequency (RF) ablation in patients with free wall accessory atrioventricular pathways, 89 patients with free wall accessory atrioventricular pathway (AP)-mediated tachyarrhythmias underwent catheter ablation. Electrophysiological parameters were similar in the patients with DC (group I, 29 patients with 30 APs) or RF (group II, 60 patients with 64 APs) ablation. Immediately after ablation, it was seen that 27 of 30 APs (90%) had been ablated successfully with DC, but two of the 27 APs had early return of conduction and received a second ablation session; three of eight APs (38%) and 53 of 56 APs (95%) were ablated successfully with RF through a small-tip (2 mm) and a large-tip (4 mm) electrode catheter, respectively. Seven of the eight APs who had a failed RF ablation later had a successful DC ablation. During the follow-up (group I, 14 to 27; group II, 8 to 14 months), all successfully ablated patients had no recurrence of tachycardia. Complications in DC ablation included transient hypotension (two patients), and pulmonary air-trapping (two patients); in RF ablation the complications included cardiac tamponade (1 patient) and suspicious aortic dissection (1 patient); myocardial injury (reflected by peak CK-MB, 34 +/- 5 vs 15 +/- 4 IU.l-1) and pro-arrhythmic effects (new atrial and ventricular arrhythmias) were more severe in those who had DC ablation. Procedure and radiation exposure time were significantly longer in RF ablation (DC, 3.6 +/- 0.2 h, 34 +/- 4 min; RF 4.0 +/- 0.4 h, 46 +/- 10 min). This study confirms that RF ablation with a large-tip electrode catheter is an effective and relatively safe non-surgical method for treatment of free wall accessory atrioventricular pathway-mediated tachyarrhythmias.

Adult↗

A comparative study of a modified catheter-mediated direct current and radiofrequency ablation on atrioventricular junction.

Conventional His-bundle ablation, performed at the site with the largest His-bundle potential, displays a high incidence of a new right bundle branch block with loss of pacemaker escape. Damage to the perinodal atrial area may decrease the injury to the His-bundle, such that the escape pacemaker activity with a narrow QRS complex is produced. This study reports data from 25 patients with drug-refractory atrial tachyarrhythmias. Nine patients (group I) received radiofrequency (RF) ablation of the atrioventricular junction (AVJ). General anesthesia was not necessary in group I patients. During a mean follow-up period of 10 months, a complete AV block persisted in 5 patients, and a first degree AV block persisted in 2 patients; these patients were asymptomatic and did not require treatment with antiarrhythmic agents. A successful direct-current (DC) ablation was performed in one of the patients with an unsuccessful RF lesion, producing a new right bundle branch block (RBBB). Sixteen patients (group II) received DC ablation of the AVJ. During a mean follow-up period of 20 months, a complete AV block persisted in 9 patients, a first degree AV block was produced in 7 patients, and a new RBBB occurred in 2 patients. Fifteen patients (94%) were asymptomatic without administration of antiarrhythmic agents. Complications, including nonsustained ventricular tachycardia (1 patient) and pericarditis (1 patient), occurred immediately after ablation in group II. Myocardial injury, reflected by creatine kinase-MB isoenzyme, was higher in group II than in group I (25 +/- 2 vs 10 +/- 1 IU/l). We conclude that (1) catheter-mediated RF ablation of the AV junction is safer than DC ablation, (2) a majority of patients with drug-refractory atrial tachyarrhythmias can be successfully treated with RF ablation and (3) failure to achieve AV junction ablation with RF does not mitigate against successful application of DC ablation.

Adult↗

Reappraisal of intermediate-term follow-up of radiofrequency ablation of accessory atrioventricular pathways for treatment of Wolff-Parkinson-White syndrome.

To evaluate the safety and efficacy of catheter mediated radiofrequency (RF) ablation in patients with Wolff-Parkinson-White syndrome, 125 patients with accessory pathway (AP) mediated tachyarrhythmias underwent RF ablation. Right-sided APs were ablated from the atrial aspect of the tricuspid annulus (all from the femoral vein approach) and the left-sided APs were ablated from the atrial or ventricular aspect of the mitral annulus. Immediately after ablation, 3 of 8 APs (38%) and 131 of 137 APs (95%) were ablated successfully with RF through a small-tip (2 mm) and a large-tip (4 mm) electrode catheter, respectively. Seven of the 11 APs where RF ablation failed had a later successful DC ablation. During follow-up (3 to 22 months), 11 of the 114 patients (10%) with successful ablation had return of accessory pathway conduction (2 had recurrence of tachycardia (2%)). Complications included transient myocardial injury (peak CK-MB 15 +/- 3 IU/l), transient proarrhythmic effects (more atrial and ventricular premature beats), accidental AV block (1 patient), cardiac tamponade (1 patient) and suspicion of aortic dissection (1 patient). In successful sessions, procedure and radiation exposure time were 3.8 +/- 0.2 h and 45 +/- 4 min, respectively. This study confirms that RF ablation with a large-tip electrode catheter is an effective and relatively safe nonsurgical method for treatment of Wolff-Parkinson-White syndrome.

Adult↗

Quantitative analysis of the coronary angiograms.

This was a two-step study performed to assess the validity of a computer system in the quantification of coronary arterial angiography (CAG). First, the in vitro study involved 10 aluminum tubes in different internal diameters but the same thickness which were pre-filled with 76% urograffin followed by cinefilm taking. Acquisition and digitization of the stop film was undertaken by a videocamera linking to a computer system. The internal diameters and mean gray levels of all tubes were measured to compare with the real diameters and areas. Second, the in vivo study calculated the percentage of stenosis by visual estimation, diameter measurement and gray level measurement by the computer system from 22 vessels in 13 coronary angiograms. The percentage of patency is the ratio of the diameter or gray level from stenotic region to that of normal region in the CAG. The calculated interobserver variability by visual estimation, diameter measurement and Mean gray level measurement were studied. Good correlation was found between measured diameters and true tube diameters (r = 0.99), and between gray level and tube areas (r = 0.94). The diameter measured by computer and the gray level had lower variability (4.0% and 5.7% respectively) than visual estimation (9.8%) did. Thus, the diameter and densitometric gray level measurements might have clinical implications to assess the coronary arterial stenosis from the coronary angiograms.

Aged↗

Follow-up of a modified catheter ablation of the atrioventricular junction in patients with atrial tachyarrhythmias.

In order to reduce cumulative energy, minimize barotrauma and infranodal injury, a modified catheter ablation technique was performed on seventeen patients. These patients had drug refractory atrial tachyarrhythmias (AT) consisting of thirteen with paroxysmal atrial fibrillation (PAf), three with sick sinus syndrome (SSS) with PAf, and one having SSS with rapid left atrial tachycardia. This technique, using the femoral approach, consisted of delivering a direct-current (DC) shock using a dual electrode configuration, to the ablation site adjacent the atrioventricular (AV) junction just before the disappearance of His deflection on the His bundle electrogram. After delivering 1-4 DV shock (mean 2.8) (cumulative energy 556 +/- 260 joules), 9 pts had first degree AV block (1st AVB) and 8 pts had complete AV block (CAVB). Only two pts had a right bundle branch block after ablation. During the clinical follow-up (15.4 +/- 2.7 months), sixteen pts were asymptomatic and were free of antiarrhythmic drugs. One pt was asymptomatic with quinidine which was ineffective before ablation. Pacemaker implantation was performed in 10 pts as a back-up for symptomatic SSS and CAVB. The results show this modified technique is relatively safe and effective.

Adult↗

Artifact simulating ventricular and atrial arrhythmia.

We describe a patient whose electrocardiograms showed ventricular tachycardia and atrial flutter which could be reproduced by arm movements. Careful review of the initiation and termination of the arrhythmia, the relation of the arrhythmia to body motion, and the associated symptoms and signs may be helpful to differentiate artifact from true arrhythmia.

Arm↗

Enalapril in congestive heart failure: acute hemodynamic and neurohumoral evaluation and short-term follow-up.

The acute efficacy of rapid loading of oral long-acting enalapril in congestive heart failure remains to be established. We evaluated the efficacy of this treatment modality in 22 patients with chronic congestive heart failure N.Y.H.A. functional class ranging from II-IV with Creatinine level less than 2 mg/dl. Following hemodynamic evaluation, there was significant favorable change in the left ventricular functional curve. Moreover, acute hemodynamic assessment showed a significant reduction in pulmonary capillary wedge pressure from 19.2 +/- 4.8 to 17.2 +/- 4.7 mmHg (p less than 0.005) and an increases in stroke volume index from 28.3 +/- 9.2 to 33.1 +/- 7.5 ml/m (p less than 0.005). After rapid enalaprilization, blood pressure fell from 127 +/- 21/78 +/- 15 to 108 +/- 21/68 +/- 15 mmHg (p less than 0.005), systemic vascular resistance from 1725 +/- 602 to 1370 +/- 376 dyne.sec.cm-5 (p less than 0.05) and pulmonary vascular resistance from 262 +/- 19 to 218 +/- 65 dyne.sec.cm-5 (p less than 0.05). Cardiac index rose significantly from 2.43 +/- 0.62 to 2.60 +/- 0.50 l/min/m2 (p less than 0.05). In terms of neurohumoral assessments, there was a significant inhibition of the renin-angiotensin-aldosterone system. Aldosterone fell from 21.3 +/- 13.4 to 9.4 +/- 8.0 ng/dl and plasma renin activity rose from 3.3 +/- 4.6 to 11.3 +/- 11.0 ng/nl/hr (p less than 0.005). Plasma norepinephrine and epinephrine levels were found to have significant reduction in addition to antidiuretic hormone concentration. During short-term trial, left ventricular ejection fraction was significantly elevated from 27.5 +/- 6% to 32.8 +/- 10.8% (p less than 0.005). Thus, this limited study clearly demonstrates the rapid administration of enalapril not only achieves inhibition of renin-angiotensin-aldosterone system but also reduces preload and afterload significantly in the failing heart. We conclude that rapid enalaprilization is an effective methodology which still needs meticulous attention, providing significant hemodynamic and symptomatic benefits in patients with chronic congestive heart failure.

Aged↗