Cardiopulmonary Assessment

Symptoms such as breathlessness, fatigue and an inability to exercise to the correct level are optimally investigated through CPET (CardioPulmonary Exercise Testing). CPET helps us to distinguish between the major cause of limitation (lung, heart, cardiovascular, muscular) and within each area, the specific cause of limitation. One test - diagnosis. Dyspnoea of unknown cause is optimally investigated with this technique. CPET is also essential in the following areas: -

Unique Diagnosis

The testing technique of CPET saves time and lowers patient risk levels as it is minimally invasive, straightforward to perform and patients find the test non-intimidating and tolerable. CPET can be uniquely utilised in the establishment of diagnosis in the following circumstances:

  • Myocardial dyskinesis with myocardial ischemia during exercise
  • Chronic heart failure due to diastolic dysfunction
  • Pulmonary Vascular Occlusive Disease without pulmonary hypertension (pulmonary vasculopathy)
  • Patent foramen ovale with right-to-left shunt during exercise
  • Pulmonary vascular disease limiting exercise in chronic obstructive pulmonary disease
  • Impaired muscle bioenergetic function
  • Psychogenic dyspnea and behavioural causes of exercise intolerance

Device Management

This unique service of the Cardiopulmonary Centre draws upon our years of experience in pacemaker/ICD device optimisation. Paced patients with shortness of breath often require assistance from their pacemaker to achieve the required heart rate for particular levels of exertion. Setup of these 'rate response' parameters has previously been calculated upon a trial-and-error basis, with experience and multiple visits required to achieve optimum pacing response to exercise. At The Cardiopulmonary Centre we are pioneering an integrative approach to device setup - with only one patient visit required both to optimise pacing parameters, and minimise pacemaker-mediated dyspnoea. The same techniques can also be applied to objectively assess optimum medication therapy in patients with a variety of medical disorders.

Pre-Operative

Patients at London Bridge Hospital awaiting major surgery will benefit from a risk-assessment evaluation preoperatively and in certain cases postoperatively. CPET has been demonstrated to indicate risk of morbidity, recovery and disability following major surgery. This is especially relevant for patients undergoing thoracotomy or cardiac surgery.

Heart Failure Assessment

The measurements taken in our cardiopulmonary exercise tests have been found to be the best predictor of survival time in chronic heart failure patients. As an adjunct to this, with CPET we can differentiate right & left heart failure and the contribution of different organ systems to exercise limitation by assessing the adequacy of the performance of various elements in the pulmonary to cellular gas exchange circuit. This is a complicated analysis, but with our extensive experience in this field we are able to provide clearly defined reporting of heart failure status. This can often provide considerable reassurance for heart failure patients.

 

References

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Treese N, MacCarter D, Akbulut O, Coutinho M, Baez M, Liebrich A, Meyer J. Ventilation and heart rate response during exercise in normals relevance for rate variable pacing. Pacing Clin Electrophysiol 1993;16: 1693-1700.