Case Study: Underlying rhythm in patient with palpitation, dizziness

Supplier: Omron
02 September, 2011

A case study on how HCG-801 revealed underlying rhythm in a patient with palpitation and dizziness.

  • Patient: 54-year-old female
  • Chief compliant: palpitation and dizziness
  • Medical history: combined rheumatic valvular disease at the age of 32
  • Case Presentation: Dr. Takeshi Shirayama, Division of Cardiology, Kyoto Prefectural University of Medicine, Japan

Clinical Course with Application of HOG-801

The patient was diagnosed with mitral stenosis and regurgitation, aortic stenois and regurgitation at the age of 32. Her symptom of heart failure was worsening with full medical treatment.

She had Open Mitral Commissurotomy at the age of 40, Mitral and Aortic Valve Replacement at the age of 44 and the second operation of Mitral Valve Replacement at the age of 47 because of the valve insufficiency. Recently, she presented with recurrent palpitation and dizziness.

Holter ECG failed to record any significant arrhythmias. A portable ECG monitor, HCG801 (OMRON, Kyoto) was provided to the patient for two months to record ECG whenever she felt symptoms. In the total of 259 ECG records, I93 ECG showed sinus tachycardia (Figure1) and 41 ECG was uncommon atrial futter (Figure2).

The heart rate was around 120lrnin in all recordings, which were observed during the palpitation attacks. R-R intervals during atrial futter were occasionally prolonged to approximately 1.5 seconds because of the decrease in conduction rate of the AV node.

Sinus arrests for 1.5 sec to 2.5 sec (Figure 3) were recorded 25 times these events were recorded at the time of dizziness.


Palpitation and dizziness are among the most frequent complaints of patients who visit medical offices. However, a Holter monitor for 24hours often fails to record the events because they occur sporadically and last only for a short time. This characteristic often makes an obstacle to early diagnosis.

Many patients decline to use a Holter monitor in summer not only because they are wet with perspiration during the monitor on, but also because they are not allowed to take a shower. A portable ECG monitor would be a good solution to overcome these problems.

The devices on the market, however, have been far from satisfaction. They can store only a couple of records in the memory. Their records were often too much noisy to be used for diagnosis. On the other hand, HGC-801 manufactured by OMRON could store hundreds of ECG even with a storage memory of an ordinary 32MB SD card in the marketplace.

This monitor is ready to use for the patients with easy instructions. Patients with repeated open heart surgery could have a higher risk of sinus node dysfunction, and atrial ventricular arrhythmias. At the same time, low cardiac output in heart failure induces sinus tachycardia, and depressed psychosomatic conditions evoke the sensation of palpitation.

Early and correct diagnosis is required to provide proper medical and psychological treatments. In this case, a beta blocker was reduced in dosage to alleviate long R-R intervals.

Catheter ablation was applied to cure atrial flutter. The patient was given some instructions to recognize the waveform pattern of sinus tachycardia on the monitor of HCG-801, on which ECG and the heart rate are displayed.

By checking ECG waveform, she was relieved by knowing that ECG was normal. This cognitive behavioural approach could successfully apply to many patients.