Characterization of Sympathetic Nerve Activity in Stress Cardiomyopathy

November 22, 2016 updated by: Anand Chockalingam, University of Missouri-Columbia

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.

Study Overview

Detailed 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.

Study Type

Interventional

Enrollment (Actual)

2

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Missouri
      • Columbia, Missouri, United States, 65212
        • University of Missouri

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

21 years to 90 years (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Description

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 Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Non-Randomized
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Study group
Subjects with documented stress cardiomyopathy who would serve as the study group. Sympathetic Nerve Activity; Mental StrCold Pressor Testess Test (Color Word Test); The Modified Oxford Technique for Baroreflex Sensitivity; Cold Pressor Test; Echocardiographic evaluation
Resting Sympathetic Nerve Activity
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.
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 Names:
  • Sodium Nitroprusside
  • Phenylephrine hydrochloride
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.
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.
Active Comparator: Control
Control subjects will be age and sex matched otherwise healthy people with no prior cardiac disease or other severe medical conditions. Sympathetic Nerve Activity; Mental Stress Test (Color Word Test); The Modified Oxford Technique for Baroreflex Sensitivity; Cold Pressor Test; Echocardiographic evaluation
Resting Sympathetic Nerve Activity
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.
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 Names:
  • Sodium Nitroprusside
  • Phenylephrine hydrochloride
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.
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.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Identifying Risk Factors and Developing Strategies to Prevent the Occurrence of Stress Cardiomyopathy in Situations Where the Likelihood in Susceptible Individuals May be High.
Time Frame: 2 years
2 years

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Anand Chockalingam, MD, University of Missouri-Columbia

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

August 1, 2009

Primary Completion (Actual)

July 1, 2012

Study Completion (Actual)

July 1, 2012

Study Registration Dates

First Submitted

January 11, 2010

First Submitted That Met QC Criteria

January 11, 2010

First Posted (Estimate)

January 13, 2010

Study Record Updates

Last Update Posted (Estimate)

November 23, 2016

Last Update Submitted That Met QC Criteria

November 22, 2016

Last Verified

October 1, 2016

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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