Kenley Jansen, LAN (Cardiac Arrhythmia) [AGL: TBD, ATD: TBD] (Explanation)
Jansen was hospitalized for two days for a cardiac arrhythmia (irregular heartbeat), but after consulting several cardiologists, he chose to start taking blood-thinning medication and was placed on the disabled list. When nerve impulses go awry, the heart can beat too fast (tachycardia), too slow (bradycardia), or irregularly. In most arrhythmia cases, people complain of a fluttering or racing heartbeat, but symptoms can also include chest pain, shortness of breath, lightheadedness, dizziness, and fainting, to name a few. Arrhythmias are a symptom of something else, and while usually harmless, the root cause of the arrhythmias still needs to be investigated to rule out life-threatening conditions.

The causes of arrhythmias are numerous and include everything from scarring of the heart caused by heart attacks to hyperthyroidism. Structural changes in the heart and blocked arteries can cause changes in the heart’s rhythm. Even the less scary sounding culprits, like stress, too little sleep, or supplements can have the same affect.

Tests to evaluate the heart include electrocardiogram (ECG or EKG), Holter monitor, and echocardiogram, along with CTs and MRIs. The most common test is the ECG, which can easily be performed in any office or medical area with the proper equipment. This is the common test seen on TV in which electrodes are placed on the chest and limbs to measure the timing and duration of the electrical phases during each heartbeat. The short test measures the peaks, valleys, and frequencies of the sinus rhythm and is evaluated by a cardiologist after completion. The Holter monitor is a portable EKG with a device smaller than a deck of cards that is worn for 24 hours to evaluate the heart’s rhythm during normal daily activities like working, sleeping, etc.

There has been a lot of discussion over the last several years about using ECGs as a screening tool for pre-participation physicals at the adolescent and collegiate levels. Studies such as this oneand this one, have shown that ECGs increase the sensitivity but not the specificity of pre-participation cardiac screenings in athletes. The number of false positives increases significantly, leading to further testing and many sleepless nights for the athletes and their families. The high incidence of mistakes and a lack of cost-effectiveness explains why this measure isn’t implemented more often. With each tragic case of sudden death, it becomes more likely that routine pre-participation screenings will be mandated at the collegiate level.

When the ECG shows an abnormality or there is concern about a structural issue with the heart, an echocardiogram can be performed. An echocardiogram allows for evaluation of the heart in real time and has the added benefit of simultaneously providing an ECG. Gel is applied to the chest to allow the ultrasonic waves to pass from the transducer through the skin with as little disruption as possible. As the ultrasonic waves bounce back to the transducer and pop up on the screen, accurate measurements of the thickness of each heart chamber can be recorded. The heart is evaluated at several different angles to ensure all the proper measurements are taken.

Jansen said he felt fluttering in his chest that worsened during Tuesday's game, and an EKG at the stadium showed an irregular heartbeat. He was taken to the hospital for further evaluation, likely including an echocardiogram, but his rhythm remained abnormal after medication. His heart had to be shocked back into rhythm, according to this report. He was placed on the disabled list, in part per Jansen's choice, and will remain on it for at least three weeks because of the blood-thinning medication.

Nate McLouth, ATL (Lower abdominal strain) [AGL: 21, ATD: -.066]
McLouth was placed on the disabled list with a lower abdominal strain, and the move was partly responsible for the Braves' trade for Michael Bourn (although McLouth’s play had something to do with that, too). After McLouth went on the disabled list, it was revealed that he has been dealing with the strain for the entire season. Even though McLouth doesn't have a significant history of abdominal or groin strains, concern about a sports hernia should rise whenever the mild pain has been present for this long. Lower abdominal strains typically take about three weeks to heal, and that's the time McLouth will likely miss if no sports hernia is found.

Nick Punto, STL (Left oblique strain) [AGL: 23, ATD: .010]
Punto was placed on the disabled list with a left oblique strain over the weekend and will likely be out for roughly a month. We've seen an increase in diagnosed oblique strains over the last several years, for a variety of reasons. The detail provided by diagnostic imaging has improved over the years and allowed for differentiation between oblique and intercostal (ribcage) strains. There has also been an increased understanding of the specific functions of the obliques, allowing the physical examination to become more focused.

There is also surely a conditioning component to this. The obliques act as a stabilizer and power generator and are a key part of the kinetic chain. Larger muscles of the legs, hips, upper back and shoulders receive a lot of strengthening attention because gains in these areas can improve performance. These may be overpowering the obliques, resulting in a strain. This trend may continue over the next few years before a conditioning program can be proven to help prevent oblique strains.

Clayton Richard, SDN (Left shoulder surgery) [AGL: 113, ATD: -.023]
Richard had surgery on his shoulder on Friday to clean up fraying in his labrum, biceps tendon, and rotator cuff. This is performed by shaving out the roughened edges until the area is smooth and friction-free. This trifecta is not uncommon in pitchers, it's just a matter of degree. Richard couldn't get the inflammation and pain out of his shoulder despite rest and physical therapy, so he decided to have the surgery. He should not be out long compared to players with larger tears within any of those structures, but he’ll certainly miss the rest of 2011.

Nelson Cruz, TEX (Right quadriceps tightness) [AGL: 1 (13DL), ATD: -.027 (+.063DL)]
Cruz had to leave Friday night's game early with left quad tightness. It was his right quad that gave him problems earlier this year, and his left hamstring that caused him to miss time last year. He ran a little bit on Saturday and seemed to tolerate it well. He's expected to return on Tuesday.

Flesh Wounds: Chris Leroux injured his left calf and was moved to the disabled list retroactive to July 28th… Derek Jeter left Sunday's game with a bruised right finger after being hit by a pitch and is day-to-day… Chris Denorfia left his game with a right hamstring strain and is also day-to-day… Clay Buchholz will meet with Dr. Robert Watkins today about his balky back. As we alluded to on Friday, it doesn't look good, and we think there might be a herniated disc involved.