Characterization of Sympathetic Nerve Activity in Stress Cardiomyopathy

Cardiomyopathy Clinical Trial

Official title:

Characterization of Sympathetic Nerve Activity in Stress Cardiomyopathy

Clinical Trial Details — Status: Terminated

Administrative data

• NCT number: NCT01048125
• Other study ID #: 1141858
• Status: Terminated
• Phase: N/A
• First received: January 11, 2010
• Last updated: November 22, 2016
• Start date: August 2009
• Est. completion date: July 2012

Study information

• Verified date: October 2016
• Source: University of Missouri-Columbia
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Interventional

Clinical Trial Summary

Stress (Takotsubo) cardiomyopathy (SC) is a peculiar form of acute, reversible myocardial dysfunction predominantly affecting the apical and mid left ventricular segments.

In this institution over the last two to three years the investigators have identified more than a dozen patients with stress cardiomyopathy. The investigators' overarching goal is to characterize these individuals with the hope of identifying risk factors and developing strategies to prevent the occurrence of SC in situations where the likelihood in susceptible individuals may be high.

Description:

Stress (Takotsubo) cardiomyopathy (SC) is a peculiar form of acute, reversible myocardial dysfunction predominantly affecting the apical and mid left ventricular segments. This was originally described in Japan but is increasingly recognized all over the world especially in older women. There is evidence to support that excess sympathetic activation and catecholamine surges are potential mechanisms that cause this temporary myocardial 'stunning'. The amount of catecholamines in circulation of patients with SC was 2 to 3-fold higher when compared to subjects with acute myocardial infarction related equivalent cardiac dysfunction [Wittstein, et al. NEJM, 2005].

In this institution over the last two to three years the investigators have identified more than a dozen patients with stress cardiomyopathy. This diagnosis has been confirmed by echocardiographic documentation of normalization of left ventricular function over a course of few days to weeks. The investigators' overarching goal is to further characterize these individuals with the hope of identifying risk factors and developing strategies to prevent the occurrence of SC in situations where the likelihood in susceptible individuals may be high.

Recruitment information / eligibility

• Status: Terminated
• Enrollment: 2
• Est. completion date: July 2012
• Est. primary completion date: July 2012
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 21 Years to 90 Years

Eligibility

Inclusion Criteria:

• Diagnosis of stress cardiomyopathy in the past

Exclusion Criteria:

• Coronary artery disease (CAD), primary coronary intervention (PCI) or coronary artery bypass graft (CABG)

• Cardiac dysfunction

• Heart failure

• Significant arrhythmias

• Severe chronic obstructive pulmonary disease (COPD)

• Diabetic neuropathy

• Pregnancy

Study Design

Allocation: Non-Randomized, Endpoint Classification: Safety Study, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Basic Science

Related Conditions & MeSH terms

• Cardiomyopathies
• Cardiomyopathy
• Takotsubo Cardiomyopathy

Intervention

Device:
• Sympathetic Nerve Activity
Resting Sympathetic Nerve Activity

Behavioral:
• Mental Stress Test (Color Word Test)
A printed word will be shown to the subject, displayed in a color different from the color it actually names. The subject will be asked to say the color that the word is printed in as quickly as possible. For example if the word "green" is written in blue ink, they will say "blue." This mental stress procedure will be used to cause brief changes in heart rate and blood pressure.

Drug:
• The Modified Oxford Technique for Baroreflex Sensitivity
Sodium nitroprusside (100 µg) will be infused intravenously as a bolus, followed 60 seconds later by a bolus of phenylephrine hydrochloride (150 µg). Infusion of nitroprusside will decrease blood pressure approximately 10-15 mmHg below baseline values. Subsequent phenylephrine infusion will increase blood pressure approximately 10-15 mmHg above baseline values. Nitroprusside and phenylephrine have been used extensively to assess baroreflex sensitivity in healthy as well as heart failure populations. Additionally, the dosages being used have been shown to minimize the risk of excessive decreases or increases in blood pressure.

Other:
• Cold Pressor Test
The subject will be asked to place their hand in ice water for 2 minutes. This procedure will be used to cause transient changes in sympathetic nerve activity, heart rate and blood pressure.

Device:
• Echocardiographic evaluation
Transthoracic echocardiography with 2D, color and pulse Doppler will be employed in all of our subjects. Baseline left ventricular function, systolic as well as diastolic, will be quantified.

Locations

Country	Name	City	State
United States	University of Missouri	Columbia	Missouri

Sponsors (1)

Lead Sponsor	Collaborator
University of Missouri-Columbia

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Identifying Risk Factors and Developing Strategies to Prevent the Occurrence of Stress Cardiomyopathy in Situations Where the Likelihood in Susceptible Individuals May be High.		2 years	No