Sports medicine pt.3

Question 1

Dynamic vs static exercise CV change

Answer 1

• Dynamic exercise vs. Static exercise
  In dynamic exercise (isotonic, aerobic), heart rate increases tremendously, while the mean blood pressure is always the same.
• In static exercise (isometric, anaerobic), heart rate and mean blood pressure increases.

Question 2

How is such high increase in cardiac output seen in exercise?

Answer 2

Because of the phenomenon of the
redistribution of the cardiac output. Blood flow to the different organs can be regulated according to the body district involved during exercise.
- At rest, blood mainly flows to GI system and 15- 20% goes to the muscles and kidneys
- However, when exercise, 80-85% of blood goes to muscles
- Proportion (4-5%) of blood going to the heart is the same, but the amount changes

Question 3

Psychological factor and cv changes

Answer 3

In neurogeneic sport activities (intense activities, F1 and skyjumping) heart rate increases in critical moments from adrenaline

Question 4

Altitudes effect on body

Answer 4

• High altitude (hyperbarism)- when you are higher from the sea level, there is a
  progressive reduction of barometric pressure and oxygen partial pressure that can lead to hypoxia
• Around 800m, O2 saturation of the arterial blood goes down to 65% and the
  peak aerobic power goes under 25%.
• Hypoxia in high altitude can cause high altitude cerebral edema (HACE). This can
  occur after body is exposed to a low- oxygen environment and before it acclimatizes. When you change altitudes without waiting for a certain amount of time (acclimatization) HACE can happen. It is a severe and potentially fatal condition. It can be seen in altitudes
  higher than 3000m. It is characterized by ataxia, fatigue and altered mental status.-

Question 5

Depth effect on body

Answer 5

Same mechanism as high altitude leads to hypoxia

Question 6

What is the effect of dehydration on CV

Answer 6

Increase in heart rate

Question 7

What is the diving reflex?

Answer 7

An ancestral reflex where contact with cold water, especially the face, causes bradycardia

Question 8

Heat effect on CV

Answer 8

Heart rate increase when the temperature increases, even when at rest, fever leads to increase in HR

Question 9

What is chronic cv change?

Answer 9

Chronic CV changes are physiological changes of both structure and function of the heart and vessels, induced
by a regular training : Athlete’s heart.

Question 10

What can chronic cv changes be divided into?

Answer 10

There are 2 types of CV changes of chronic adaptation:
- Central changes (heart)
- Peripheral changes (blood vessels

Question 11

What are central cv changes in chronic exercise?

Answer 11

• Increased heart volume (higher stroke volume)
• Lower heart rate (both at rest and at submaximal working loads
  The heart grows in dimension, athletes have bigger and more efficient hearts, with normal systolic and diastolic function, called Athletes’s cardiomegaly, hypertrophy

Question 12

HR of blue whale

Answer 12

In nature the blue whale has the biggest heart: 180 kg, with a SV of 220L. it
has indeed an HR of 8 or 10 beats per minute

Question 13

What does enlargement of the heart in athletes depend on?

Answer 13

There’re physiological limits for the enlargement of the heart in the athletes and they depend on:
- Body size of the animal
- Muscular energy demands: the size of the heart depends on the size of muscular mass involved during
activities

Question 14

Which animal has the smallest heart to body weight ratio?

Answer 14

Humans

Question 15

Type of heart growth in power cs endurance athletes

Answer 15

In endurance athletes (like cross
country runners), the heart was characterized by eccentric hypertrophy with big cavity and moderate
hypertrophy of LV walls while in power athletes (weight lifters) it was characterized by a concentric
hypertrophy with similar cavities to the one of sedentary people but with a considerably thicker LV
wall.

Question 16

Characteristics of heart enlargement in athletes heart vs pathological conditions

Answer 16

• Athlete’s heart becomes larger
  harmoniously, bilaterally, symmetrically and involving all the chambers.
• Most pathological conditions did
  not have this symmetry like in hypertrophic cardiomyopathy
  (affecting mainly the LV), dilated cardiomyopathy (LV) and
  arrhythmogenic cardiomyopathy (affecting primarily but not
  exclusively the RV).
  The symmetry is an important

Question 17

Cardiac hypertrophy in white vs black athletes

Answer 17

Black athletes have more cardiac hypertrophy than the white athletes, making them more efficient

Question 18

LV diastolic diamter and left ventricular thickness values in athletes

Answer 18

• The upper limit of the LV diastolic
  diameter is 63mm, while most adult male athletes have 58-59mm, but we can also see some extreme cases up to 70mm.
• For the hypertrophy, the limit for the LV
  wall thickness at 13mm even if there can be cases of extreme hypertrophy with values reaching up to 16mm especially in athletes practicing sports that require a very high
  energy.
• In junior athletes: These limits are
  lower in junior athletes even if they are also highly trained. The limit for the LV
  diastolic diameter is 60mm, and 64mm can be seen in some rare cases. For LV wall thickness the limit is 12mm and there are rare cases of 14mm.

Question 19

Most CV diseases in the young that don’t allow them to do sports

Answer 19

In italy, Most of our diseases, CV diseases in the young, have an arrhythmic risk problem. They do not die
from heart rupture but from arrhythmia

Question 20

How do GPs make money in Italy?

Answer 20

every GP takes the money based on the number of assigned pt, independently on whether they come to the clinic or not

Question 21

What is the top cause of sudden cardiac death in the USA?

Answer 21

Hypertrophic cardiomyopathy is the first cause of SD in athletes in the US.

Question 22

What can the Causes of sudden death in athletes be divided into

Answer 22

SD in athletes during sports is mainly due to 2 reasons:
* Arrhythmic death: usually due to ventricular tachycardia that leads to ventricular fibrillation
and finally results in death
* Mechanical death: mainly aortic rupture

Question 23

Sudden death from impact to chest

Answer 23

• Commotio cordis is a phenomenon in which a sudden blunt impact to the chest causes sudden death in the absence of cardiac damage.
• Resuscitation, once thought to be nearly universally unsuccessful, has now been demonstrated to be successful in up to 35% of commotio cordis victims.
• The initial rhythm is ventricular fibrillation in those in whom a defibrillator is used relatively early
  after the event. Currently, the outcome of resuscitation in commotio cordis appears to be very similar to that for resuscitation in other forms of sudden cardiac death.
• Commotio cordis is a primary arrhythmic event that occurs when the
  mechanical energy that is generated is confined to a small area of the
  precordium and profoundly alters the electrical stability of the
  myocardium, resulting in ventricular fibrillation. It is usually, although not invariably, fatal. In only about 25% (1/4) of cases (internet says 35%), cardiopulmonary resuscitation, or
  defibrillation results in survival - a low percentage, considering that commotion cordis is defined by the absence of structural heart disease.