Permanent impairment case study - cardiovascular

The following case studies relate to injuries to the Cardiovascular System.

More detailed information regarding the assessment of injuries to the cardiovascular system may be found at Chapter 8 of the permanent impairment guidelines and Chapter 6 of the AMA4 Guidelines.

We make no warranties or representation about the accuracy or completeness of the information contained in these Case Studies. It should be noted that the information contained herein is not provided as a substitute for legal advice.

Case Study # Brief Description Primary Body System Secondary Body System
C1 Aortic tear injury Cardiovascular  
C2 Myocardial contusion Cardiovascular  

This matter was subject to review by a Medical Review Panel. These are the Review Panel’s findings.

Claimant’s Date of Birth: 15 February 1986

Date of Motor Accident: 26 January 2006

Injuries: Thoracic aorta - tear
Panel Findings

The panel noted that there is adequate contemporaneous medical evidence to support an injury to the thoracic aorta due to the MVA. The panel noted a significant amount of documentation within the hospital notes from Royal North Shore Hospital.

The panel noted the statement in Assessor X’s Statement of Reasons regarding the insertion of the endovascular stent, which resulted in aortic obstruction or acquired coarctation of the thoracic aorta causing mild systolic hypertension.

The panel considered all methods of assessment of permanent impairment for this condition, as provided in the AMA Guides for the Evaluation of Permanent Impairment, 4th Edition under Chapter 6 - the cardiovascular system, and also cross referenced to Chapter 8, Page 49 of the Permanent Impairment Guidelines of the Motor Accident Authority, 1 October 2007.

The panel considered the assessment of this injury by analogy and comparing it to congenital heart disease, and assessing the coarctation by analogy, under this table, was the most appropriate method of assessment. The panel noted the history and the physical findings and noted in particular that there was “a decrease in femoral pulses with radio-femoral delay and blood pressure was lower. The recorded blood pressure on the right lower limb was slightly lower than the recorded pressure in the right upper limb, all consistent with mild aortic obstruction due to the endovascular stent. There was a grade 2 aortic systolic murmur heard between the shoulder blades at T2/3 consistent with mild aortic stenosis of the upper descending aorta”.

Panel Decision

The panel considered rating this injury for permanent impairment under Table 8. The panel was particularly cognisant of the examples listed on Page 181 (AMA Guides) under Example 1 where the diagnosis was mild pulmonary valve stenosis and noted that the recommendation was to consider this as a Class 1 impairment in the upper impairment of the scale. The example quoted 9% impairment of whole person. The panel considered that the presentation of the claimant was not dissimilar to the example quoted, and thus, considered that the appropriate impairment for this injury would be 9% whole person impairment.

The panel did not consider further deterioration in this determination and was cognisant of Paragraphs 1.23 and 1.24 of the Impairment Guidelines, where “the evaluation should only consider the impairment as it is at the time of the assessment and the evaluation should not include any allowance for a predicted deterioration.”

The panel was of the opinion that if deterioration of the injury occurred, the claimant was likely to enter into a higher category such as Class 2, if complications developed, which would result in an even higher impairment.

Thus, the panel concluded that the impairment for the thoracic aorta - tear, based on the claimant’s current presentation, was 9% WPI.

The whole person permanent impairment of the injuries caused by the accident was calculated as follows:

  Body Part or System AMA Guides/ MAA Guidelines References (chapter/ page/table) Stabilised (YES/NO) Current %WPI* %WPI* from pre-existing OR subsequent causes %WPI* due to motor accident
1. Cardiovascular system Table 8, Page 181 Yes 9 0 9

* %WPI = percentage whole person impairment

Determination Regarding the Degree of Whole Person Impairment of the Injured Person as a Result of the Injuries Caused by the Motor Accident

The total percentage whole person permanent impairment for assessed injuries caused by the motor accident is 9%. Therefore the total whole person impairment is not greater than 10%.

Injuries: Myocardial contusion

The claimant was a 56 year old male front seat passenger. The car he was travelling in hit a tree and he sustained a chest contusion, among other injuries.

On arrival at hospital the claimant’s blood pressure and oxygen saturation were stable. Heart sounds were normal and bruising and abrasions were noted to the left shoulder area, consistent with a seatbelt injury. An E.C.G showed widespread ST segment elevation indicating a possible myocardial contusion.

He was admitted to Coronary Care and was monitored overnight. During the night, he had several episodes of second degree heart block and transient bursts of atrial fibrillation and all reverted to normal sinus rhythm. Blood tests were ordered and the cardiac enzymes were recorded as normal.

A cardiac echo showed normal ventricular size with normal systolic function. The treating Cardiologist thought that the transient atrial fibrillation and heart block were a result of the seatbelt contusion injury.

Continued cardiac monitoring showed no further abnormalities and the claimant was discharged. Follow up consultations with a Cardiologist showed no further problems. The claimant raised the chest/heart injury in his reply forms and a Cardiac Assessor was appointed to resolve the dispute.

Clinical Examination

In accordance with clause 8.7 of the MAA Permanent Impairment Guidelines 2007, the claimant attended with all available diagnostic test results. On examination, he had normal blood pressure, normal 12 lead ECG, his pulse was 68 and regular. The claimant had not had any further episodes of arrhythmias since the accident. There were no complaints of chest pain, shortness of breath or any limitation in daily living activities.

Impairment Evaluation

The Assessor used the AMA4 Guides Cardiovascular System Chapter 6, Table 12, p195, Impairment Classification for Cardiac Arrhythmias, and Chapter 8 of the MAA Guidelines.

Table 12 is divided into four classes, depending on the severity of the arrhythmias. The Assessor considered that the claimant fell into Class 1, 0% - 9%.

The criteria for Class 1 are:

  • The patient is asymptomatic during ordinary activities and a cardiac arrhythmia is documented by ECG; and
  • There is no evidence of organic heart disease; OR
  • The patient has recovered from surgery or a catheter procedure to correct arrhythmia and the above criteria are met.

As the claimant met none of the above criteria above, he was rated as 0% wholeperson impairment.